diff --git a/desktop/src/app/AppShellContext.tsx b/desktop/src/app/AppShellContext.tsx
index 4a64de0cb2..533ba16fb3 100644
--- a/desktop/src/app/AppShellContext.tsx
+++ b/desktop/src/app/AppShellContext.tsx
@@ -14,7 +14,7 @@ type AppShellContextValue = {
     readAt: string | null | undefined,
     options?: { topLevelOnly?: boolean },
   ) => void;
-  markChannelUnread: (channelId: string) => void;
+  markChannelUnread: (channelId: string) => boolean;
   openBrowseChannels: () => void;
   openCreateChannel: () => void;
   openChannelManagement: (channelId?: string) => void;
@@ -56,7 +56,7 @@ type AppShellContextValue = {
 const AppShellContext = React.createContext<AppShellContextValue>({
   markAllChannelsRead: () => {},
   markChannelRead: () => {},
-  markChannelUnread: () => {},
+  markChannelUnread: () => false,
   openBrowseChannels: () => {},
   openCreateChannel: () => {},
   openChannelManagement: () => {},
diff --git a/desktop/src/features/channels/nip-rs-unread-ui.test.mjs b/desktop/src/features/channels/nip-rs-unread-ui.test.mjs
index e53a34dee5..1f427e076e 100644
--- a/desktop/src/features/channels/nip-rs-unread-ui.test.mjs
+++ b/desktop/src/features/channels/nip-rs-unread-ui.test.mjs
@@ -29,6 +29,7 @@ import {
 } from "./readStateOverride.ts";
 import { forcedUnreadStore } from "./forcedUnreadStore.ts";
 import { resolveChannelReadMarker } from "./useUnreadChannels.ts";
+import { applyMarkUnreadDividerOverlay } from "./ui/useChannelUnreadState.ts";
 
 // ── localStorage mock ────────────────────────────────────────────────────────
 
@@ -138,83 +139,138 @@ test("applyOverrideUnread_load_incomplete_returns_false", () => {
 });
 
 // ── Tests: applyOverrideRead ─────────────────────────────────────────────────
+//
+// New semantics (NIP-RS:537-539):
+//   1. !isReadStateReady → fail closed (overrideStillActive)
+//   2. isReadStateReady + null liveness → known absence (overrideCleared, no C-bump)
+//   3. isReadStateReady + register exists → ALWAYS attempt C-bump, then re-check
 
-test("applyOverrideRead_null_liveness_pre_init_returns_overrideStillActive", () => {
-  // null ≠ inactive: pre-init must fail closed
-  const result = applyOverrideRead("ch-1", {
-    markChannelUnread: () => ({ success: true }),
-    markChannelRead: () => {
-      throw new Error("should not be called");
-    },
-    getOverrideLiveness: () => null,
-  });
-  assert.equal(result, "overrideStillActive");
-});
-
-test("applyOverrideRead_inactive_liveness_returns_overrideCleared_without_c_bump", () => {
-  // Frontier advance made override inactive; no C-bump needed
-  let bumpCalled = false;
-  const result = applyOverrideRead("ch-1", {
-    markChannelUnread: () => ({ success: true }),
-    markChannelRead: () => {
-      bumpCalled = true;
-      return { success: true };
-    },
-    getOverrideLiveness: () => ({ active: false, frontier: 200 }),
-  });
-  assert.equal(result, "overrideCleared");
-  assert.equal(bumpCalled, false, "C-bump not called when already inactive");
-});
-
-test("applyOverrideRead_active_liveness_success_then_inactive_returns_overrideCleared", () => {
-  // Active → C-bump succeeds → re-read shows inactive
-  let callCount = 0;
-  const result = applyOverrideRead("ch-1", {
+// Helper: builds a minimal OverrideAPIs object with sensible defaults.
+function makeApis(overrides = {}) {
+  return {
+    isReadStateReady: true,
     markChannelUnread: () => ({ success: true }),
     markChannelRead: () => ({ success: true }),
-    getOverrideLiveness: () => {
-      callCount++;
-      // First call (pre-bump check): active. Second call (post-bump): inactive.
-      return callCount === 1
-        ? { active: true, frontier: 50 }
-        : { active: false, frontier: 50 };
-    },
-  });
+    getOverrideLiveness: () => null,
+    ...overrides,
+  };
+}
+
+test("applyOverrideRead_manager_not_ready_fails_closed_overrideStillActive", () => {
+  // Step 1: !isReadStateReady → fail closed without calling manager.
+  let bumped = false;
+  const result = applyOverrideRead(
+    "ch-1",
+    makeApis({
+      isReadStateReady: false,
+      markChannelRead: () => {
+        bumped = true;
+        return { success: true };
+      },
+      getOverrideLiveness: () => ({ active: true, frontier: 50 }),
+    }),
+  );
+  assert.equal(result, "overrideStillActive");
+  assert.equal(bumped, false, "C-bump must not fire when manager not ready");
+});
+
+test("applyOverrideRead_ready_null_liveness_no_register_overrideCleared", () => {
+  // Step 2: ready + null liveness = known no-register → cleared, no C-bump.
+  let bumped = false;
+  const result = applyOverrideRead(
+    "ch-1",
+    makeApis({
+      isReadStateReady: true,
+      markChannelRead: () => {
+        bumped = true;
+        return { success: true };
+      },
+      getOverrideLiveness: () => null,
+    }),
+  );
+  assert.equal(result, "overrideCleared");
+  assert.equal(bumped, false, "no C-bump when no register exists");
+});
+
+test("applyOverrideRead_inactive_register_cbump_attempted_then_clears", () => {
+  // Step 3 with inactive register: C-bump must be attempted (NIP-RS:537-539).
+  // After the bump, post-call liveness is still inactive → overrideCleared.
+  let bumped = false;
+  const result = applyOverrideRead(
+    "ch-1",
+    makeApis({
+      isReadStateReady: true,
+      markChannelRead: () => {
+        bumped = true;
+        return { success: true };
+      },
+      getOverrideLiveness: () => ({ active: false, frontier: 200 }),
+    }),
+  );
+  assert.equal(result, "overrideCleared");
+  assert.equal(bumped, true, "C-bump attempted even when already inactive");
+});
+
+test("applyOverrideRead_active_liveness_success_then_inactive_overrideCleared", () => {
+  // Active register → C-bump succeeds → re-read shows inactive → cleared.
+  let callCount = 0;
+  const result = applyOverrideRead(
+    "ch-1",
+    makeApis({
+      isReadStateReady: true,
+      markChannelRead: () => ({ success: true }),
+      getOverrideLiveness: () => {
+        callCount++;
+        return callCount === 1
+          ? { active: true, frontier: 50 }
+          : { active: false, frontier: 50 };
+      },
+    }),
+  );
   assert.equal(result, "overrideCleared");
 });
 
-test("applyOverrideRead_active_liveness_uint32_overflow_returns_overrideStillActive", () => {
-  // Active → C-bump refuses → re-read still active → overrideStillActive
-  let _callCount = 0;
-  const result = applyOverrideRead("ch-1", {
-    markChannelUnread: () => ({ success: true }),
-    markChannelRead: () => ({ success: false, reason: "uint32_overflow" }),
-    getOverrideLiveness: () => {
-      _callCount++;
-      return { active: true, frontier: 50 };
-    },
-  });
+test("applyOverrideRead_active_liveness_load_incomplete_overrideStillActive", () => {
+  // Active → C-bump refuses (load_incomplete) → liveness still active → retained.
+  const result = applyOverrideRead(
+    "ch-1",
+    makeApis({
+      isReadStateReady: true,
+      markChannelRead: () => ({ success: false, reason: "load_incomplete" }),
+      getOverrideLiveness: () => ({ active: true, frontier: 50 }),
+    }),
+  );
   assert.equal(result, "overrideStillActive");
 });
 
-test("applyOverrideRead_active_liveness_load_incomplete_returns_overrideStillActive", () => {
-  // Active → C-bump refuses (load_incomplete) → overrideStillActive
-  const result = applyOverrideRead("ch-1", {
-    markChannelUnread: () => ({ success: true }),
-    markChannelRead: () => ({ success: false, reason: "load_incomplete" }),
-    getOverrideLiveness: () => ({ active: true, frontier: 50 }),
-  });
-  assert.equal(result, "overrideStillActive");
+test("applyOverrideRead_already_inactive_race_overrideCleared", () => {
+  // already_inactive race: cleared by another device → silent success.
+  const result = applyOverrideRead(
+    "ch-1",
+    makeApis({
+      isReadStateReady: true,
+      markChannelRead: () => ({ success: false, reason: "already_inactive" }),
+      getOverrideLiveness: () => ({ active: true, frontier: 50 }),
+    }),
+  );
+  assert.equal(result, "overrideCleared");
 });
 
-test("applyOverrideRead_already_inactive_race_returns_overrideCleared", () => {
-  // already_inactive: cleared by another device between liveness check and
-  // clear call — treat as silent success.
-  const result = applyOverrideRead("ch-1", {
-    markChannelUnread: () => ({ success: true }),
-    markChannelRead: () => ({ success: false, reason: "already_inactive" }),
-    getOverrideLiveness: () => ({ active: true, frontier: 50 }),
-  });
+test("applyOverrideRead_post_call_null_liveness_treated_as_cleared", () => {
+  // Post-bump liveness is null (register deleted remotely) → overrideCleared.
+  let callCount = 0;
+  const result = applyOverrideRead(
+    "ch-1",
+    makeApis({
+      isReadStateReady: true,
+      markChannelRead: () => ({ success: true }),
+      getOverrideLiveness: () => {
+        callCount++;
+        // Pre-call: active register. Post-call: register gone (null).
+        return callCount === 1 ? { active: true, frontier: 50 } : null;
+      },
+    }),
+  );
   assert.equal(result, "overrideCleared");
 });
 
@@ -372,6 +428,37 @@ test("applyOverrideUnread_refusal_caller_must_not_mutate_overlay", () => {
   );
 });
 
+// ── Tests: applyMarkUnreadDividerOverlay (active-channel handleMarkUnread) ────
+//
+// This is the extracted production transition from handleMarkUnread in
+// useChannelUnreadState. Tests verify: success adds to overlay, refusal does not.
+
+test("applyMarkUnreadDividerOverlay_success_adds_to_overlay_returns_true", () => {
+  const overlay = new Set();
+  const result = applyMarkUnreadDividerOverlay(
+    "ch-active",
+    () => true, // markFn returns true = accepted
+    overlay,
+  );
+  assert.equal(result, true, "returns true on acceptance");
+  assert.equal(overlay.has("ch-active"), true, "adds to overlay on success");
+});
+
+test("applyMarkUnreadDividerOverlay_refusal_does_not_add_to_overlay_returns_false", () => {
+  const overlay = new Set();
+  const result = applyMarkUnreadDividerOverlay(
+    "ch-refused",
+    () => false, // markFn returns false = refused
+    overlay,
+  );
+  assert.equal(result, false, "returns false on refusal");
+  assert.equal(
+    overlay.has("ch-refused"),
+    false,
+    "overlay not mutated on refusal",
+  );
+});
+
 // ── Tests: markAllChannelsRead partial refusal pattern ────────────────────────
 //
 // Witnesses that per-channel gating in markAllChannelsRead correctly clears
@@ -387,6 +474,7 @@ test("applyOverrideRead_partial_refusal_pattern_clears_only_inactive", () => {
   };
   let clearCallCount = 0;
   const apis = {
+    isReadStateReady: true,
     markChannelUnread: () => ({ success: true }),
     markChannelRead: (id) => {
       clearCallCount++;
diff --git a/desktop/src/features/channels/readStateOverride.ts b/desktop/src/features/channels/readStateOverride.ts
index 9052334c41..99f51078be 100644
--- a/desktop/src/features/channels/readStateOverride.ts
+++ b/desktop/src/features/channels/readStateOverride.ts
@@ -42,6 +42,7 @@ export function overrideErrorMessage(
 
 /** Slice-2 override APIs from ReadStateManager, proxied through useReadState. */
 export type OverrideAPIs = {
+  isReadStateReady: boolean;
   markChannelUnread: (channelId: string) => MarkResult;
   markChannelRead: (channelId: string) => MarkResult;
   getOverrideLiveness: (channelId: string) => OverrideLiveness | null;
@@ -68,13 +69,13 @@ export function applyOverrideUnread(
 /**
  * Outcome of the explicit mark-read transition for one channel.
  *
- * `overrideCleared` — the NIP-RS override is now known inactive (either it was
- *   already inactive, or the C-bump succeeded and the resulting liveness is
- *   inactive). Callers should clear local presentation.
+ * `overrideCleared` — the NIP-RS override is now known inactive (no register
+ *   exists, the frontier deactivated it, or the C-bump succeeded). Callers
+ *   should clear local presentation.
  *
- * `overrideStillActive` — the C-bump was refused (or returned a result where
- *   liveness remains active / unknown). Callers must NOT clear local unread
- *   presentation; the spec MUST at NIP-RS:537-539 requires success only when
+ * `overrideStillActive` — the manager is unavailable (fail-closed) or the
+ *   C-bump was refused and liveness remains active. Callers MUST NOT clear
+ *   local unread presentation; NIP-RS:537-539 requires success only when
  *   resulting override_active == false.
  */
 export type OverrideReadOutcome = "overrideCleared" | "overrideStillActive";
@@ -83,47 +84,48 @@ export type OverrideReadOutcome = "overrideCleared" | "overrideStillActive";
  * Attempt to clear the NIP-RS override for `channelId` as part of an explicit
  * mark-read transition. Models the transition as a single outcome:
  *
- *   1. If liveness is null (pre-init): fail-closed — return overrideStillActive
- *      without calling the manager (null ≠ inactive).
- *   2. If liveness is inactive: return overrideCleared immediately (no C-bump
- *      needed; the frontier advance already made override_active == false).
- *   3. If liveness is active: call markChannelRead, then re-read liveness.
- *      - If resulting liveness is inactive (or already_inactive race): cleared.
- *      - If the manager refused for any reason that keeps liveness active:
- *        show a toast and return overrideStillActive.
- *
- * Special edge (permitted by spec): if the caller's frontier advance made
- * F > B, liveness is already inactive before the C-bump — this is detected at
- * step 2, so no error toast fires in that case.
+ *   1. Manager unavailable (!isReadStateReady): fail-closed —
+ *      return overrideStillActive (manager unavailable ≠ no register).
+ *   2. liveness === null (ready but no register): return overrideCleared
+ *      (known absence; no C-bump needed).
+ *   3. liveness exists (active or inactive): always call markChannelRead —
+ *      spec NIP-RS:537-539 requires the C-bump even when the frontier already
+ *      deactivated the override. Then re-read liveness.
+ *      a. Resulting liveness inactive (or already_inactive race): cleared.
+ *      b. uint32 refusal AND F > B (frontier already deactivated): cleared,
+ *         no error toast (representable C-bump was not possible, frontier
+ *         already provides the inactive verdict).
+ *      c. Other refusal keeping liveness active: show toast, overrideStillActive.
  */
 export function applyOverrideRead(
   channelId: string,
   apis: OverrideAPIs,
 ): OverrideReadOutcome {
+  // Step 1: manager unavailable → fail closed.
+  if (!apis.isReadStateReady) return "overrideStillActive";
+
   const liveness = apis.getOverrideLiveness(channelId);
 
-  // Pre-init: null ≠ inactive. Fail closed.
-  if (liveness === null) return "overrideStillActive";
+  // Step 2: ready but no register at all → known absence, cleared.
+  if (liveness === null) return "overrideCleared";
 
-  // Already inactive (frontier advance made F > B, or never active).
-  if (!liveness.active) return "overrideCleared";
-
-  // Active override: attempt the C-bump.
+  // Step 3: register exists — always attempt the C-bump (NIP-RS:537-539).
   const result = apis.markChannelRead(channelId);
 
   if (!result.success && result.reason === "already_inactive") {
-    // Race condition: cleared by another device between our liveness check and
-    // the clear call. Silent success.
+    // Race: cleared by another device between our check and the call.
     return "overrideCleared";
   }
 
   // Re-read liveness after the attempt.
   const afterLiveness = apis.getOverrideLiveness(channelId);
-  if (afterLiveness !== null && !afterLiveness.active) {
+  // Covers: successful C-bump (inactive after), F>B deactivation (inactive after),
+  // and uint32 refusal where F>B already deactivated the register.
+  if (afterLiveness === null || !afterLiveness.active) {
     return "overrideCleared";
   }
 
-  // Refused and still active (or unknown post-call liveness).
+  // Refused and still active.
   if (!result.success) {
     const msg = overrideErrorMessage("read", result.reason);
     if (msg) toast.error(msg);
diff --git a/desktop/src/features/channels/ui/useChannelUnreadState.ts b/desktop/src/features/channels/ui/useChannelUnreadState.ts
index 298a52f54d..843f342d36 100644
--- a/desktop/src/features/channels/ui/useChannelUnreadState.ts
+++ b/desktop/src/features/channels/ui/useChannelUnreadState.ts
@@ -26,6 +26,26 @@ import { isConversationalUnreadKind } from "@/shared/constants/kinds";
 
 import { useWelcomeInitialUnreadSuppression } from "./useWelcomeInitialUnreadSuppression";
 
+/**
+ * Pure helper: apply the mark-unread divider overlay.
+ *
+ * Calls `markFn(channelId)` and, if it returns true (accepted), adds the
+ * channel to the `overlay` set. Returns the same boolean so callers can gate
+ * any additional side-effects on success.
+ *
+ * Extracted for testability: `handleMarkUnread` calls this instead of
+ * inlining the same two-step logic.
+ */
+export function applyMarkUnreadDividerOverlay(
+  channelId: string,
+  markFn: (id: string) => boolean,
+  overlay: Set<string>,
+): boolean {
+  const accepted = markFn(channelId);
+  if (accepted) overlay.add(channelId);
+  return accepted;
+}
+
 type UseChannelUnreadStateOptions = {
   activeChannelId: string | null;
   timelineMessages: TimelineMessage[];
@@ -36,7 +56,7 @@ type UseChannelUnreadStateOptions = {
   openThreadMessages?: MainTimelineEntry[];
   getChannelReadAt: (channelId: string) => number | null;
   getMessageReadAt: (messageId: string) => number | null;
-  markChannelUnread: (channelId: string) => void;
+  markChannelUnread: (channelId: string) => boolean;
   markMessageRead: (messageId: string, timestamp: number) => void;
   isThreadMuted: (rootId: string) => boolean;
   readStateVersion: number;
@@ -404,19 +424,11 @@ export function useChannelUnreadState({
 
   const handleMarkUnread = React.useCallback(() => {
     if (!activeChannelId) return;
-    // Call the manager first — the sidebar dot is driven by liveness, not the
-    // session overlay. Only update the session overlay after the manager call
-    // so a refused mark-unread does not spuriously suppress the timeline marker.
-    markChannelUnread(activeChannelId);
-    // The `forcedUnreadRef` overlay here gates the timeline "New" divider
-    // suppression (see computeChannelUnreadMarker above). We must not set it
-    // before the manager call or on refusal. Since `markChannelUnread` has a
-    // void return type at this boundary, we rely on readStateVersion bumping
-    // on success (manager subscribe fires → outer hook re-renders → liveness
-    // is now active). The overlay is intentionally NOT set here — the divider
-    // suppression is driven by liveness via isActiveChannelForcedUnread only
-    // when the sidebar dot confirms active override state. Setting the overlay
-    // unconditionally would suppress the divider even on a refused call.
+    applyMarkUnreadDividerOverlay(
+      activeChannelId,
+      markChannelUnread,
+      forcedUnreadRef.current,
+    );
     forceUnreadRender();
   }, [activeChannelId, markChannelUnread]);
 
diff --git a/desktop/src/features/channels/useUnreadChannels.ts b/desktop/src/features/channels/useUnreadChannels.ts
index a47898252e..add6e2a2fb 100644
--- a/desktop/src/features/channels/useUnreadChannels.ts
+++ b/desktop/src/features/channels/useUnreadChannels.ts
@@ -149,15 +149,12 @@ export function useUnreadChannels(
   } = options;
   const activeChannelId = activeChannel?.id ?? null;
   const normalizedPubkey = pubkey?.toLowerCase() ?? null;
-  // Scoped relay key for activity storage; empty string when relay not yet known
-  // so rows from an unknown relay never load into the wrong community.
+  // Scoped relay key; empty string when relay not yet known.
   const normalizedRelayUrl = relayUrlOption
     ? normalizeRelayUrl(relayUrlOption)
     : "";
-  // Single identity for the in-memory thread-activity buffer — computed once
-  // per render and used at reset, both writers, and the return fence. The
-  // helper returns "" when either value is absent, which never matches a valid
-  // loaded scope, so the fence returns [] until the buffer is seeded.
+  // Activity scope key: "" when pubkey/relay absent (never matches a valid
+  // loaded scope, so the fence returns [] until the buffer is seeded).
   const currentActivityScope = activityScopeKey(
     normalizedPubkey,
     normalizedRelayUrl,
@@ -176,14 +173,19 @@ export function useUnreadChannels(
     markChannelRead: markChannelOverrideRead,
     getOverrideLiveness,
   } = useReadState(pubkey, relayClient);
-  // Stable object wrapping the three override APIs.
   const overrideApis = React.useMemo<OverrideAPIs>(
     () => ({
+      isReadStateReady,
       markChannelUnread: markChannelOverrideUnread,
       markChannelRead: markChannelOverrideRead,
       getOverrideLiveness,
     }),
-    [getOverrideLiveness, markChannelOverrideRead, markChannelOverrideUnread],
+    [
+      getOverrideLiveness,
+      isReadStateReady,
+      markChannelOverrideRead,
+      markChannelOverrideUnread,
+    ],
   );
 
   // Observed "latest external trigger event" per channel — derived relay evidence
@@ -335,13 +337,11 @@ export function useUnreadChannels(
     [markContextRead, overrideApis, pubkey],
   );
 
-  // Manually mark a channel unread (right-click → "mark unread"). Publishes a
-  // NIP-RS override event to the relay (S bump + B set), then updates the
-  // local cache. Shows a toast on failure (budget exhaustion, counter overflow,
-  // or incomplete load).
+  // Manually mark a channel unread (right-click). Returns true when the manager
+  // accepted (use to gate session-local UI overlays on success only).
   const markChannelUnread = React.useCallback(
-    (channelId: string) => {
-      if (!applyOverrideUnread(channelId, overrideApis)) return;
+    (channelId: string): boolean => {
+      if (!applyOverrideUnread(channelId, overrideApis)) return false;
       if (
         persistForcedUnread(
           channelId,
@@ -351,6 +351,7 @@ export function useUnreadChannels(
         )
       )
         bumpLatestVersion();
+      return true;
     },
     [getOwnTimestamp, overrideApis, pubkey],
   );
diff --git a/desktop/src/features/communities/communityUnreadObserver.test.mjs b/desktop/src/features/communities/communityUnreadObserver.test.mjs
index 6386d06102..1b3a71adbf 100644
--- a/desktop/src/features/communities/communityUnreadObserver.test.mjs
+++ b/desktop/src/features/communities/communityUnreadObserver.test.mjs
@@ -641,7 +641,7 @@ test("fetchCommunityUnread threaded reply whose root is in mutedRootIds → hasU
   assert.deepEqual(result, { hasUnread: false, mentionCount: 0 });
 });
 
-// ── Forced-unread persistence gate tests ─────────────────────────────────
+// ── Override register authoritative source tests ──────────────────────────
 
 // A relay that serves one channel (CHANNEL_ID) as a member channel,
 // with no read state and no incoming events.
@@ -727,8 +727,12 @@ function quietRelayWithReadState(readAtSeconds) {
   ]);
 }
 
-test("fetchCommunityUnread forced-unread channel lights rail dot (hasUnread:true)", async () => {
+test("fetchCommunityUnread stored active register lights rail (hasUnread:true)", async () => {
+  // Authoritative source (a): stored register is active (S=1,C=0,B=0 with F=0).
+  // The fetch returns no override events — stored register is the authority.
   const relay = quietRelay();
+  // Active register: S=1, C=0, B=0 (baseline), frontier=0 → override_active = true
+  const storedRegisters = new Map([[CHANNEL_ID, { s: 1, c: 0, b: 0 }]]);
 
   const result = await fetchCommunityUnread({
     client: relay,
@@ -737,20 +741,18 @@ test("fetchCommunityUnread forced-unread channel lights rail dot (hasUnread:true
     decryptReadState: async (v) => v,
     decryptMutes: async (v) => v,
     readThreadRelationships: readRelationships(),
-    // Forced-unread map: CHANNEL_ID forced when marker was null (no prior read)
-    readForcedUnread: () => ({ [CHANNEL_ID]: null }),
+    readStoredRegisters: () => storedRegisters,
   });
 
   assert.deepEqual(result, { hasUnread: true, mentionCount: 0 });
 });
 
-test("fetchCommunityUnread forced-unread channel not in member list → hasUnread:false", async () => {
-  // The channel is marked forced-unread but the user is not a member of ANY
-  // channel — forced-unread is not consulted when the channel set is empty.
-  const relay = relayFor([
-    // 1. member events — empty
-    () => [],
-  ]);
+test("fetchCommunityUnread stored tombstoned register does NOT light rail (hasUnread:false)", async () => {
+  // Authoritative source (a): stored register is tombstoned (S=1,C=1 → S=C, inactive).
+  // Local cache cannot contradict this — must not light the dot.
+  const relay = quietRelay();
+  // Tombstoned: S=1, C=1, B=0 → override_active = false (S > C fails: 1 > 1 = false)
+  const storedRegisters = new Map([[CHANNEL_ID, { s: 1, c: 1, b: 0 }]]);
 
   const result = await fetchCommunityUnread({
     client: relay,
@@ -759,13 +761,38 @@ test("fetchCommunityUnread forced-unread channel not in member list → hasUnrea
     decryptReadState: async (v) => v,
     decryptMutes: async (v) => v,
     readThreadRelationships: readRelationships(),
-    readForcedUnread: () => ({ [CHANNEL_ID]: null }),
+    readStoredRegisters: () => storedRegisters,
   });
 
   assert.deepEqual(result, { hasUnread: false, mentionCount: 0 });
 });
 
-test("fetchCommunityUnread forced-unread channel that is also muted → hasUnread:false", async () => {
+test("fetchCommunityUnread old active register beyond horizon still lights rail", async () => {
+  // An active register that is older than the 7-day horizon must still light
+  // the rail. The fetch is tag-free and has no `since`, so it returns no
+  // events here, but the stored projection (authoritative source a) is used.
+  const relay = quietRelay();
+  const VERY_OLD_FRONTIER = 1; // far beyond any 7-day horizon
+  // S=1, C=0, B=VERY_OLD_FRONTIER, and frontier=VERY_OLD_FRONTIER → active
+  const storedRegisters = new Map([
+    [CHANNEL_ID, { s: 1, c: 0, b: VERY_OLD_FRONTIER }],
+  ]);
+
+  const result = await fetchCommunityUnread({
+    client: relay,
+    pubkey: PUBKEY,
+    nowSeconds: 100 + 7 * 24 * 3600 + 1, // past the old 7-day cutoff
+    decryptReadState: async (v) => v,
+    decryptMutes: async (v) => v,
+    readThreadRelationships: readRelationships(),
+    readStoredRegisters: () => storedRegisters,
+  });
+
+  assert.deepEqual(result, { hasUnread: true, mentionCount: 0 });
+});
+
+test("fetchCommunityUnread no stored register and empty fetch → falls through to relay gate", async () => {
+  // No stored registers, no override event fetched, but a real unread event exists.
   const relay = relayFor([
     // 1. member events
     () => [
@@ -787,16 +814,20 @@ test("fetchCommunityUnread forced-unread channel that is also muted → hasUnrea
     ],
     // 3. visibility
     () => [],
-    // 4. read-state (parallel with mutes)
+    // 4. read-state — empty
     () => [],
-    // 5. mutes — CHANNEL_ID is muted
+    // 5. mutes
+    () => [],
+    // 6. unread events — one real unread
     () => [
       event({
-        pubkey: PUBKEY,
-        content: mutesContent([CHANNEL_ID]),
+        id: "real-unread".padEnd(64, "0"),
+        created_at: 20,
+        tags: [["h", CHANNEL_ID]],
       }),
     ],
-    // No per-channel fetches expected — muted channel is skipped
+    // 7. mention events
+    () => [],
   ]);
 
   const result = await fetchCommunityUnread({
@@ -806,15 +837,33 @@ test("fetchCommunityUnread forced-unread channel that is also muted → hasUnrea
     decryptReadState: async (v) => v,
     decryptMutes: async (v) => v,
     readThreadRelationships: readRelationships(),
-    // CHANNEL_ID is both forced-unread AND muted — mute wins
-    readForcedUnread: () => ({ [CHANNEL_ID]: null }),
+    readStoredRegisters: () => new Map(), // no stored registers
+  });
+
+  assert.deepEqual(result, { hasUnread: true, mentionCount: 0 });
+});
+
+test("fetchCommunityUnread channel not in member list → hasUnread:false", async () => {
+  // No members — register lookup is never reached.
+  const relay = relayFor([
+    () => [], // member events empty
+  ]);
+
+  const result = await fetchCommunityUnread({
+    client: relay,
+    pubkey: PUBKEY,
+    nowSeconds: 100,
+    decryptReadState: async (v) => v,
+    decryptMutes: async (v) => v,
+    readThreadRelationships: readRelationships(),
+    readStoredRegisters: () => new Map([[CHANNEL_ID, { s: 1, c: 0, b: 0 }]]),
   });
 
   assert.deepEqual(result, { hasUnread: false, mentionCount: 0 });
 });
 
-test("fetchCommunityUnread readForcedUnread returns empty map → falls through to relay gate", async () => {
-  // No forced-unread, but there IS a real unread event → hasUnread:true via relay
+test("fetchCommunityUnread active register muted channel → hasUnread:false", async () => {
+  // Override is active, but the channel is muted — mute wins.
   const relay = relayFor([
     // 1. member events
     () => [
@@ -838,18 +887,14 @@ test("fetchCommunityUnread readForcedUnread returns empty map → falls through
     () => [],
     // 4. read-state
     () => [],
-    // 5. mutes
-    () => [],
-    // 6. unread events
+    // 5. mutes — CHANNEL_ID is muted
     () => [
       event({
-        id: "real-unread".padEnd(64, "0"),
-        created_at: 20,
-        tags: [["h", CHANNEL_ID]],
+        pubkey: PUBKEY,
+        content: mutesContent([CHANNEL_ID]),
       }),
     ],
-    // 7. mention events
-    () => [],
+    // No per-channel fetches expected — muted channel is skipped
   ]);
 
   const result = await fetchCommunityUnread({
@@ -859,33 +904,19 @@ test("fetchCommunityUnread readForcedUnread returns empty map → falls through
     decryptReadState: async (v) => v,
     decryptMutes: async (v) => v,
     readThreadRelationships: readRelationships(),
-    readForcedUnread: () => ({}), // empty — no forced-unread
-  });
-
-  assert.deepEqual(result, { hasUnread: true, mentionCount: 0 });
-});
-
-test("fetchCommunityUnread forced-unread + synced marker advanced PAST baseline → hasUnread:false", async () => {
-  // markerAtWhenForced = 50, observed readAt = 100 (100 > 50 → cross-device read wins)
-  const relay = quietRelayWithReadState(100);
-
-  const result = await fetchCommunityUnread({
-    client: relay,
-    pubkey: PUBKEY,
-    nowSeconds: 200,
-    decryptReadState: async (v) => v,
-    decryptMutes: async (v) => v,
-    readThreadRelationships: readRelationships(),
-    // Forced at marker=50; synced marker is now 100 — covers the force
-    readForcedUnread: () => ({ [CHANNEL_ID]: 50 }),
+    // Active register, but channel is muted — mute wins
+    readStoredRegisters: () => new Map([[CHANNEL_ID, { s: 1, c: 0, b: 0 }]]),
   });
 
   assert.deepEqual(result, { hasUnread: false, mentionCount: 0 });
 });
 
-test("fetchCommunityUnread forced-unread + synced marker NOT advanced past baseline → hasUnread:true", async () => {
-  // markerAtWhenForced = 100, observed readAt = 100 (equal → force still stands)
+test("fetchCommunityUnread frontier advance deactivates stored register → hasUnread:false", async () => {
+  // Register: S=1, C=0, B=50 (active only when F<=50).
+  // Fetched frontier: 100 > 50 → override_active = false.
   const relay = quietRelayWithReadState(100);
+  // B=50 means active only when F<=50; fetched frontier is 100 → inactive
+  const storedRegisters = new Map([[CHANNEL_ID, { s: 1, c: 0, b: 50 }]]);
 
   const result = await fetchCommunityUnread({
     client: relay,
@@ -894,27 +925,7 @@ test("fetchCommunityUnread forced-unread + synced marker NOT advanced past basel
     decryptReadState: async (v) => v,
     decryptMutes: async (v) => v,
     readThreadRelationships: readRelationships(),
-    // Forced at marker=100; synced marker is still 100 — no newer read
-    readForcedUnread: () => ({ [CHANNEL_ID]: 100 }),
-  });
-
-  assert.deepEqual(result, { hasUnread: true, mentionCount: 0 });
-});
-
-test("fetchCommunityUnread forced-unread with null baseline + synced marker present → hasUnread:false", async () => {
-  // markerAtWhenForced = null (no marker at force-time), but readAt = 50 now
-  // A cross-device read appeared after the force → do NOT light the dot
-  const relay = quietRelayWithReadState(50);
-
-  const result = await fetchCommunityUnread({
-    client: relay,
-    pubkey: PUBKEY,
-    nowSeconds: 200,
-    decryptReadState: async (v) => v,
-    decryptMutes: async (v) => v,
-    readThreadRelationships: readRelationships(),
-    // Forced when no marker existed; a cross-device read has since appeared
-    readForcedUnread: () => ({ [CHANNEL_ID]: null }),
+    readStoredRegisters: () => storedRegisters,
   });
 
   assert.deepEqual(result, { hasUnread: false, mentionCount: 0 });
diff --git a/desktop/src/features/communities/communityUnreadObserver.ts b/desktop/src/features/communities/communityUnreadObserver.ts
index 698a0355b4..95161da63d 100644
--- a/desktop/src/features/communities/communityUnreadObserver.ts
+++ b/desktop/src/features/communities/communityUnreadObserver.ts
@@ -1,15 +1,14 @@
 import { makeRootIdStore } from "@/features/channels/unreadRootIdStore";
-import {
-  forcedUnreadStore,
-  type ForcedUnreadMap,
-} from "@/features/channels/forcedUnreadStore";
 import { DM_NOTIFIABLE_EVENT_KINDS } from "@/features/channels/isDmNotifiableKind";
 import { mergeReadStateEventsStructured } from "@/features/channels/readState/readStateSnapshot";
 import {
   isOverrideActive,
   maxReadAt,
   msgContextKey,
+  type OverrideRegister,
 } from "@/features/channels/readState/readStateFormat";
+import { readStoredReadState } from "@/features/channels/readState/readStateStorage";
+import { deduplicateByCoordinate } from "@/features/channels/readState/readStateFencedLoader";
 import {
   getThreadReference,
   isBroadcastReply,
@@ -87,7 +86,6 @@ const METADATA_LIMIT = 1000;
 const UNREAD_EXISTENCE_LIMIT = 50;
 const MENTION_COUNT_LIMIT = 100;
 const READ_STATE_FETCH_LIMIT = 500;
-const READ_STATE_HORIZON_SECONDS = 7 * 24 * 60 * 60;
 
 export type CommunityUnreadObserverResult = {
   hasUnread: boolean;
@@ -160,16 +158,26 @@ export async function fetchCommunityUnread(args: {
   decryptReadState?: (ciphertext: string) => Promise<string>;
   decryptMutes?: (ciphertext: string) => Promise<string>;
   readThreadRelationships?: (pubkey: string) => ThreadRelationships;
-  readForcedUnread?: (pubkey: string) => ForcedUnreadMap;
+  /** Authoritative source (a): persisted override register projection. Defaults
+   *  to `readStoredReadState(pubkey).overrideRegisters`. Inject for tests. */
+  readStoredRegisters?: (
+    pubkey: string,
+  ) => ReadonlyMap<string, OverrideRegister>;
 }): Promise<CommunityUnreadObserverResult> {
   const { client, pubkey } = args;
   const normalizedPubkey = pubkey.toLowerCase();
-  const nowSeconds = args.nowSeconds ?? Math.floor(Date.now() / 1_000);
   const decryptMutes = args.decryptMutes ?? nip44DecryptFromSelf;
   const readRelationships =
     args.readThreadRelationships ?? defaultReadThreadRelationships;
-  const readForcedUnread =
-    args.readForcedUnread ?? ((pk) => forcedUnreadStore.read(pk));
+  const getStoredRegisters =
+    args.readStoredRegisters ??
+    ((pk: string) => {
+      try {
+        return readStoredReadState(pk).overrideRegisters;
+      } catch {
+        return new Map<string, OverrideRegister>();
+      }
+    });
 
   const channels = await fetchObservedChannels(client, pubkey);
   if (channels.length === 0) {
@@ -177,11 +185,11 @@ export async function fetchCommunityUnread(args: {
   }
 
   const [readStateEvents, mutesEvents] = await Promise.all([
+    // Override state is exempt from finite-horizon fetching: a register may be
+    // older than seven days and must not be missed. Tag-free, no `since` filter.
     client.fetchEvents({
       kinds: [KIND_READ_STATE],
       authors: [pubkey],
-      "#t": ["read-state"],
-      since: nowSeconds - READ_STATE_HORIZON_SECONDS,
       limit: READ_STATE_FETCH_LIMIT,
     }),
     client.fetchEvents({
@@ -192,12 +200,34 @@ export async function fetchCommunityUnread(args: {
     }),
   ]);
 
+  // Authoritative source (b): coordinate-deduped registers decoded from fetched
+  // events. deduplicateByCoordinate retains greatest created_at, lowest id.
   const readState = await mergeReadStateEventsStructured(
-    readStateEvents,
+    deduplicateByCoordinate(readStateEvents),
     pubkey,
     args.decryptReadState,
   );
 
+  // Authoritative source (a): persisted full-state projection from the manager's
+  // last complete load. Merge with source (b): max() per field, so a register
+  // present in only one source is retained.
+  const storedRegisters = getStoredRegisters(normalizedPubkey);
+  const mergedOverrides = new Map<string, OverrideRegister>(
+    readState.overrides,
+  );
+  for (const [rawCtx, stored] of storedRegisters) {
+    const fetched = mergedOverrides.get(rawCtx);
+    if (!fetched) {
+      mergedOverrides.set(rawCtx, stored);
+    } else {
+      mergedOverrides.set(rawCtx, {
+        s: Math.max(fetched.s, stored.s),
+        c: Math.max(fetched.c, stored.c),
+        b: Math.max(fetched.b, stored.b),
+      });
+    }
+  }
+
   let mutedIds = new Set<string>();
   if (mutesEvents.length > 0) {
     try {
@@ -218,11 +248,6 @@ export async function fetchCommunityUnread(args: {
     mutedRootIds,
   } = readRelationships(normalizedPubkey);
 
-  // Channels manually marked unread on this device — local cache of the NIP-RS
-  // override layer. Used only as a fast path; the authoritative verdict is the
-  // structured override register evaluated against the merged frontier.
-  const forcedUnreadMap = readForcedUnread(normalizedPubkey);
-
   let hasUnread = false;
   let mentionCount = 0;
 
@@ -232,26 +257,13 @@ export async function fetchCommunityUnread(args: {
     // Compute readAt from the merged frontiers.
     const readAt = readState.frontiers.get(channel.id) ?? null;
 
-    // Forced-unread: evaluate the structured override register using the same
-    // override_active(S, C, B, F) predicate as the active-community path. The
-    // local cache entry is a hint only — the register is the authoritative source.
+    // Override liveness: evaluate the merged authoritative register.
+    // "No register in fetched events" is ambiguity, not absence — the local
+    // cache is NOT a fallback verdict source here.
     if (!hasUnread) {
-      const reg = readState.overrides.get(channel.id);
+      const reg = mergedOverrides.get(channel.id);
       if (reg !== undefined && isOverrideActive(reg, readAt ?? 0)) {
         hasUnread = true;
-      } else if (
-        reg === undefined &&
-        Object.hasOwn(forcedUnreadMap, channel.id)
-      ) {
-        // No register in fetched events: fall back to the local cache as a best-
-        // effort hint (override event may not have reached the relay yet).
-        const markerAtWhenForced = forcedUnreadMap[channel.id];
-        if (
-          readAt === null ||
-          (markerAtWhenForced !== null && readAt <= markerAtWhenForced)
-        ) {
-          hasUnread = true;
-        }
       }
     }