diff --git a/desktop/src/features/communities/resolveCommunityUpdateResult.test.mjs b/desktop/src/features/communities/resolveCommunityUpdateResult.test.mjs
index 0a52ef845..37f24e59d 100644
--- a/desktop/src/features/communities/resolveCommunityUpdateResult.test.mjs
+++ b/desktop/src/features/communities/resolveCommunityUpdateResult.test.mjs
@@ -5,7 +5,10 @@
 import assert from "node:assert/strict";
 import test from "node:test";
 
-import { resolveCommunityUpdateResult } from "./useCommunities.tsx";
+import {
+  resolveCommunityReplacement,
+  resolveCommunityUpdateResult,
+} from "./useCommunities.tsx";
 
 const COMMUNITIES = [
   {
@@ -56,7 +59,10 @@ test("resolveCommunityUpdateResult_duplicate_relay_returns_duplicate", () => {
   const result = resolveCommunityUpdateResult(COMMUNITIES, "ws-1", "ws-1", {
     relayUrl: "wss://relay-b.example.com",
   });
-  assert.deepEqual(result, { kind: "duplicate-relay" });
+  assert.deepEqual(result, {
+    kind: "duplicate-relay",
+    existingCommunityId: "ws-2",
+  });
 });
 
 test("resolveCommunityUpdateResult_not_found_returns_not_found", () => {
@@ -105,3 +111,22 @@ test("resolveCommunityUpdateResult_same_relay_url_is_not_duplicate_of_self", ()
   });
   assert.deepEqual(result, { kind: "unchanged" });
 });
+
+test("resolveCommunityReplacement_drops_stale_entry_and_keeps_replacement", () => {
+  const result = resolveCommunityReplacement(COMMUNITIES, "ws-1", "ws-2");
+
+  assert.equal(result.kind, "replaced");
+  assert.deepEqual(result.communities, [COMMUNITIES[1]]);
+  assert.equal(result.removedCommunity, COMMUNITIES[0]);
+  assert.equal(result.replacementCommunity, COMMUNITIES[1]);
+});
+
+test("resolveCommunityReplacement_rejects_missing_or_identical_entries", () => {
+  assert.deepEqual(
+    resolveCommunityReplacement(COMMUNITIES, "missing", "ws-2"),
+    { kind: "not-found" },
+  );
+  assert.deepEqual(resolveCommunityReplacement(COMMUNITIES, "ws-1", "ws-1"), {
+    kind: "not-found",
+  });
+});
diff --git a/desktop/src/features/communities/ui/CommunityChangeOverlay.tsx b/desktop/src/features/communities/ui/CommunityChangeOverlay.tsx
index d4ebcdc06..26e678acb 100644
--- a/desktop/src/features/communities/ui/CommunityChangeOverlay.tsx
+++ b/desktop/src/features/communities/ui/CommunityChangeOverlay.tsx
@@ -1,19 +1,24 @@
 import * as React from "react";
 
+import type { Community } from "../types";
 import { useCommunities } from "../useCommunities";
+import { Button } from "@/shared/ui/button";
 import { CommunityEditForm } from "./CommunityEditForm";
 
 type CommunityChangeOverlayProps = {
   onClose: () => void;
-  onUpdated?: (name: string, relayUrl: string) => void;
+  onUpdated?: (community: Community, replaced: boolean) => void;
 };
 
 export function CommunityChangeOverlay({
   onClose,
   onUpdated,
 }: CommunityChangeOverlayProps) {
-  const { activeCommunity, updateCommunity } = useCommunities();
+  const { activeCommunity, communities, replaceCommunity, updateCommunity } =
+    useCommunities();
   const [error, setError] = React.useState<string | null>(null);
+  const [duplicateCommunity, setDuplicateCommunity] =
+    React.useState<Community | null>(null);
   const overlayRef = React.useRef<HTMLDivElement>(null);
 
   // Focus trap: focus the overlay on mount
@@ -36,13 +41,14 @@ export function CommunityChangeOverlay({
     (name: string, relayUrl: string) => {
       if (!activeCommunity) return;
       setError(null);
+      setDuplicateCommunity(null);
       const result = updateCommunity(activeCommunity.id, { name, relayUrl });
       switch (result.kind) {
         case "unchanged":
           onClose();
           break;
         case "updated":
-          onUpdated?.(name, relayUrl);
+          onUpdated?.({ ...activeCommunity, name, relayUrl }, false);
           // If reinit is needed, the communityKey change will trigger a remount.
           // If not (name-only), just close.
           if (!result.requiresReinit) {
@@ -50,17 +56,43 @@ export function CommunityChangeOverlay({
           }
           // If requiresReinit, the tree remounts — overlay unmounts naturally.
           break;
-        case "duplicate-relay":
-          setError("Another community already uses this relay URL.");
+        case "duplicate-relay": {
+          const existingCommunity = communities.find(
+            (community) => community.id === result.existingCommunityId,
+          );
+          if (existingCommunity) {
+            setDuplicateCommunity(existingCommunity);
+          } else {
+            setError("Community not found.");
+          }
           break;
+        }
         case "not-found":
           setError("Community not found.");
           break;
       }
     },
-    [activeCommunity, onClose, onUpdated, updateCommunity],
+    [activeCommunity, communities, onClose, onUpdated, updateCommunity],
   );
 
+  const handleReplace = React.useCallback(() => {
+    if (!activeCommunity || !duplicateCommunity) return;
+    const result = replaceCommunity(activeCommunity.id, duplicateCommunity.id);
+    if (result.kind !== "replaced") {
+      setDuplicateCommunity(null);
+      setError("Community not found.");
+      return;
+    }
+    onUpdated?.(result.replacementCommunity, true);
+    onClose();
+  }, [
+    activeCommunity,
+    duplicateCommunity,
+    onClose,
+    onUpdated,
+    replaceCommunity,
+  ]);
+
   if (!activeCommunity) return null;
 
   return (
@@ -93,6 +125,30 @@ export function CommunityChangeOverlay({
         {error ? (
           <p className="mt-4 text-center text-sm text-destructive">{error}</p>
         ) : null}
+        {duplicateCommunity ? (
+          <div className="mt-4 rounded-xl border border-amber-500/30 bg-amber-500/10 p-4 text-sm">
+            <p className="font-medium text-foreground">
+              {duplicateCommunity.name} already uses this relay URL.
+            </p>
+            <p className="mt-1 text-muted-foreground">
+              Remove {activeCommunity.name} from this device and switch to the
+              saved community? This does not change either relay.
+            </p>
+            <div className="mt-4 flex justify-end gap-2">
+              <Button
+                onClick={() => setDuplicateCommunity(null)}
+                size="sm"
+                type="button"
+                variant="outline"
+              >
+                Keep editing
+              </Button>
+              <Button onClick={handleReplace} size="sm" type="button">
+                Replace stale entry
+              </Button>
+            </div>
+          </div>
+        ) : null}
       </div>
     </div>
   );
diff --git a/desktop/src/features/communities/useCommunities.tsx b/desktop/src/features/communities/useCommunities.tsx
index 48668a374..86527ef54 100644
--- a/desktop/src/features/communities/useCommunities.tsx
+++ b/desktop/src/features/communities/useCommunities.tsx
@@ -24,7 +24,16 @@ import { clearSavedCommunitySnapshot } from "@/features/agents/activeAgentTurnsS
 export type UpdateCommunityResult =
   | { kind: "updated"; requiresReinit: boolean }
   | { kind: "unchanged" }
-  | { kind: "duplicate-relay" }
+  | { kind: "duplicate-relay"; existingCommunityId: string }
+  | { kind: "not-found" };
+
+export type ReplaceCommunityResult =
+  | {
+      kind: "replaced";
+      communities: Community[];
+      removedCommunity: Community;
+      replacementCommunity: Community;
+    }
   | { kind: "not-found" };
 
 /**
@@ -43,12 +52,13 @@ export function resolveCommunityUpdateResult(
   const current = communities.find((w) => w.id === id);
   if (!current) return { kind: "not-found" };
 
-  if (
-    updates.relayUrl !== undefined &&
-    updates.relayUrl !== current.relayUrl &&
-    communities.some((w) => w.id !== id && w.relayUrl === updates.relayUrl)
-  ) {
-    return { kind: "duplicate-relay" };
+  if (updates.relayUrl !== undefined && updates.relayUrl !== current.relayUrl) {
+    const existing = communities.find(
+      (w) => w.id !== id && w.relayUrl === updates.relayUrl,
+    );
+    if (existing) {
+      return { kind: "duplicate-relay", existingCommunityId: existing.id };
+    }
   }
 
   const hasChange =
@@ -72,6 +82,32 @@ export function resolveCommunityUpdateResult(
   return { kind: "updated", requiresReinit: backendFieldsChanged };
 }
 
+/**
+ * Remove a stale local community entry in favor of another saved entry.
+ * This is local-only recovery: it never mutates either relay.
+ */
+export function resolveCommunityReplacement(
+  communities: Community[],
+  removedId: string,
+  replacementId: string,
+): ReplaceCommunityResult {
+  const removedCommunity = communities.find((w) => w.id === removedId);
+  const replacementCommunity = communities.find((w) => w.id === replacementId);
+  if (
+    !removedCommunity ||
+    !replacementCommunity ||
+    removedCommunity.id === replacementCommunity.id
+  ) {
+    return { kind: "not-found" };
+  }
+  return {
+    kind: "replaced",
+    communities: communities.filter((w) => w.id !== removedCommunity.id),
+    removedCommunity,
+    replacementCommunity,
+  };
+}
+
 export type UseCommunitiesReturn = {
   communities: Community[];
   activeCommunity: Community | null;
@@ -81,6 +117,11 @@ export type UseCommunitiesReturn = {
   addCommunity: (community: Community) => string;
   clearCommunities: () => void;
   removeCommunity: (id: string) => void;
+  /** Drop a stale local entry and activate an already-saved replacement. */
+  replaceCommunity: (
+    removedId: string,
+    replacementId: string,
+  ) => ReplaceCommunityResult;
   switchCommunity: (id: string) => void;
   /** Force the active community to re-init (e.g. after a deep-link reconnect). */
   reconnectCommunity: () => void;
@@ -196,6 +237,35 @@ function useCommunitiesInternal(): UseCommunitiesReturn {
     [activeId, communities],
   );
 
+  const replaceCommunity = useCallback(
+    (removedId: string, replacementId: string): ReplaceCommunityResult => {
+      const result = resolveCommunityReplacement(
+        communitiesRef.current,
+        removedId,
+        replacementId,
+      );
+      if (result.kind !== "replaced") return result;
+
+      const removedRelayStillUsed = result.communities.some(
+        (community) => community.relayUrl === result.removedCommunity.relayUrl,
+      );
+      if (!removedRelayStillUsed) {
+        removeSelfProfileCachesForRelay(result.removedCommunity.relayUrl);
+        removeChannelSnapshotForRelay(result.removedCommunity.relayUrl);
+        removeMessageSnapshotsForRelay(result.removedCommunity.relayUrl);
+      }
+      clearSavedCommunitySnapshot(result.removedCommunity.id);
+
+      communitiesRef.current = result.communities;
+      saveCommunities(result.communities);
+      saveActiveCommunityId(result.replacementCommunity.id);
+      setCommunitiesState(result.communities);
+      setActiveId(result.replacementCommunity.id);
+      return result;
+    },
+    [],
+  );
+
   const switchCommunity = useCallback(
     (id: string) => {
       if (id === activeId) return;
@@ -249,6 +319,7 @@ function useCommunitiesInternal(): UseCommunitiesReturn {
     addCommunity,
     clearCommunities,
     removeCommunity,
+    replaceCommunity,
     switchCommunity,
     reconnectCommunity,
     updateCommunity,
diff --git a/desktop/src/features/onboarding/communityOnboarding.test.mjs b/desktop/src/features/onboarding/communityOnboarding.test.mjs
index 8ffa59ec8..15a0cb382 100644
--- a/desktop/src/features/onboarding/communityOnboarding.test.mjs
+++ b/desktop/src/features/onboarding/communityOnboarding.test.mjs
@@ -3,6 +3,7 @@ import test from "node:test";
 
 import {
   clearCommunityOnboardingTransaction,
+  communityReplacementOnboardingPatch,
   loadCommunityOnboardingTransaction,
   markCommunityOnboardingComplete,
   startCommunityOnboarding,
@@ -147,3 +148,39 @@ test("completion is scoped by relay and pubkey and preserves legacy gate", () =>
   );
   assert.equal(storage.getItem("buzz-onboarding-complete.v1:pubkey"), "true");
 });
+
+test("community replacement retargets a wedged transaction", () => {
+  const storage = createMemoryStorage();
+  const transaction = startCommunityOnboarding(
+    { source: "add-community", relayUrl: "wss://stale.example" },
+    storage,
+  );
+  const connected = updateCommunityOnboardingTransaction(
+    transaction,
+    {
+      communityId: "stale-id",
+      previousCommunityId: "previous-id",
+      addedCommunity: true,
+      stage: "profile",
+      error: "not a relay member",
+    },
+    storage,
+  );
+
+  const repaired = updateCommunityOnboardingTransaction(
+    connected,
+    communityReplacementOnboardingPatch({
+      id: "saved-id",
+      name: "Saved community",
+      relayUrl: "wss://saved.example",
+    }),
+    storage,
+  );
+
+  assert.equal(repaired.communityId, "saved-id");
+  assert.equal(repaired.previousCommunityId, "saved-id");
+  assert.equal(repaired.addedCommunity, false);
+  assert.equal(repaired.relayUrl, "wss://saved.example");
+  assert.equal(repaired.stage, "connecting");
+  assert.equal(repaired.error, undefined);
+});
diff --git a/desktop/src/features/onboarding/communityOnboarding.tsx b/desktop/src/features/onboarding/communityOnboarding.tsx
index 1f0fe45ec..5ef65fa36 100644
--- a/desktop/src/features/onboarding/communityOnboarding.tsx
+++ b/desktop/src/features/onboarding/communityOnboarding.tsx
@@ -2,6 +2,7 @@ import {
   deriveCommunityName,
   normalizeRelayUrl,
 } from "@/features/communities/communityStorage";
+import type { Community } from "@/features/communities/types";
 import { setLocalStorageItemWithRecovery } from "@/shared/lib/localStorageQuota";
 
 const STORAGE_KEY = "buzz-community-onboarding-transaction.v1";
@@ -76,6 +77,21 @@ export type StartCommunityOnboardingInput = {
   policyReceipt?: string;
 };
 
+/** Retarget a wedged onboarding transaction to an existing saved community. */
+export function communityReplacementOnboardingPatch(
+  replacement: Pick<Community, "id" | "name" | "relayUrl">,
+): CommunityOnboardingTransactionPatch {
+  return {
+    communityId: replacement.id,
+    communityName: replacement.name,
+    relayUrl: replacement.relayUrl,
+    addedCommunity: false,
+    previousCommunityId: replacement.id,
+    stage: "connecting",
+    error: undefined,
+  };
+}
+
 function canonicalRelayUrl(rawRelayUrl: string) {
   const trimmed = rawRelayUrl.trim();
   const withScheme = /^(ws|wss):\/\//i.test(trimmed)
diff --git a/desktop/src/features/onboarding/ui/CommunityOnboardingFlow.tsx b/desktop/src/features/onboarding/ui/CommunityOnboardingFlow.tsx
index e09fd8404..a5765adf5 100644
--- a/desktop/src/features/onboarding/ui/CommunityOnboardingFlow.tsx
+++ b/desktop/src/features/onboarding/ui/CommunityOnboardingFlow.tsx
@@ -3,6 +3,7 @@ import { useQueryClient } from "@tanstack/react-query";
 import { Plus, Users, X } from "lucide-react";
 
 import {
+  communityReplacementOnboardingPatch,
   markCommunityOnboardingComplete,
   useCommunityOnboarding,
 } from "@/features/onboarding/communityOnboarding";
@@ -273,13 +274,18 @@ export function CommunityOnboardingFlow({
         {isCommunityChangeOpen ? (
           <CommunityChangeOverlay
             onClose={() => setIsCommunityChangeOpen(false)}
-            onUpdated={(communityName, updatedRelayUrl) => {
-              update({
-                communityName,
-                relayUrl: updatedRelayUrl,
-                stage: "connecting",
-                error: undefined,
-              });
+            onUpdated={(updatedCommunity, replaced) => {
+              update(
+                replaced
+                  ? communityReplacementOnboardingPatch(updatedCommunity)
+                  : {
+                      communityId: updatedCommunity.id,
+                      communityName: updatedCommunity.name,
+                      relayUrl: updatedCommunity.relayUrl,
+                      stage: "connecting",
+                      error: undefined,
+                    },
+              );
               setIsMembershipDenied(false);
             }}
           />