diff --git a/keyserver/src/responders/website-responders.js b/keyserver/src/responders/website-responders.js
--- a/keyserver/src/responders/website-responders.js
+++ b/keyserver/src/responders/website-responders.js
@@ -238,7 +238,7 @@
   inviteLinksStore: inviteLinksStoreValidator,
   lastCommunicatedPlatformDetails: t.irreducible(
     'default lastCommunicatedPlatformDetails',
-    _isEqual({}),
+    _isEqual(null),
   ),
   keyserverStore: keyserverStoreValidator,
 });
@@ -605,7 +605,7 @@
     _persist: null,
     commServicesAccessToken: null,
     inviteLinksStore: inviteLinksStorePromise,
-    lastCommunicatedPlatformDetails: {},
+    lastCommunicatedPlatformDetails: null,
     keyserverStore: keyserverStorePromise,
   });
   const validatedInitialReduxState = validateOutput(
diff --git a/lib/reducers/last-communicated-platform-details-reducer.js b/lib/reducers/last-communicated-platform-details-reducer.js
--- a/lib/reducers/last-communicated-platform-details-reducer.js
+++ b/lib/reducers/last-communicated-platform-details-reducer.js
@@ -6,30 +6,23 @@
   logInActionTypes,
   registerActionTypes,
 } from '../actions/user-actions.js';
-import type { LastCommunicatedPlatformDetails } from '../types/device-types';
+import type { PlatformDetails } from '../types/device-types';
 import type { BaseAction } from '../types/redux-types';
 import { getConfig } from '../utils/config.js';
 
 export default function reduceLastCommunicatedPlatformDetails(
-  state: LastCommunicatedPlatformDetails,
+  state: ?PlatformDetails,
   action: BaseAction,
-  currentURLPrefix: string,
-): LastCommunicatedPlatformDetails {
+): ?PlatformDetails {
   if (
     action.type === logInActionTypes.success ||
     action.type === siweAuthActionTypes.success ||
     action.type === registerActionTypes.success
   ) {
-    return {
-      ...state,
-      [currentURLPrefix]: getConfig().platformDetails,
-    };
+    return getConfig().platformDetails;
   }
   if (action.type === updateLastCommunicatedPlatformDetailsActionType) {
-    return {
-      ...state,
-      ...action.payload,
-    };
+    return action.payload;
   }
   return state;
 }
diff --git a/lib/reducers/master-reducer.js b/lib/reducers/master-reducer.js
--- a/lib/reducers/master-reducer.js
+++ b/lib/reducers/master-reducer.js
@@ -148,7 +148,6 @@
       lastCommunicatedPlatformDetails: reduceLastCommunicatedPlatformDetails(
         state.lastCommunicatedPlatformDetails,
         action,
-        state.keyserverStore.keyserverInfos[ashoatKeyserverID].urlPrefix,
       ),
       keyserverStore,
     },
diff --git a/lib/selectors/server-calls.js b/lib/selectors/server-calls.js
--- a/lib/selectors/server-calls.js
+++ b/lib/selectors/server-calls.js
@@ -8,7 +8,7 @@
   urlPrefixSelector,
   connectionSelector,
 } from './keyserver-selectors.js';
-import type { LastCommunicatedPlatformDetails } from '../types/device-types.js';
+import type { PlatformDetails } from '../types/device-types.js';
 import type { AppState } from '../types/redux-types.js';
 import type {
   ConnectionInfo,
@@ -22,7 +22,7 @@
   +sessionID: ?string,
   +currentUserInfo: ?CurrentUserInfo,
   +connectionStatus: ?ConnectionStatus,
-  +lastCommunicatedPlatformDetails: LastCommunicatedPlatformDetails,
+  +lastCommunicatedPlatformDetails: ?PlatformDetails,
 };
 
 const serverCallStateSelector: (state: AppState) => ServerCallState =
@@ -39,7 +39,7 @@
       sessionID: ?string,
       currentUserInfo: ?CurrentUserInfo,
       connectionInfo: ?ConnectionInfo,
-      lastCommunicatedPlatformDetails: LastCommunicatedPlatformDetails,
+      lastCommunicatedPlatformDetails: ?PlatformDetails,
     ) => ({
       cookie,
       urlPrefix,
diff --git a/lib/socket/socket.react.js b/lib/socket/socket.react.js
--- a/lib/socket/socket.react.js
+++ b/lib/socket/socket.react.js
@@ -582,7 +582,7 @@
     if (shouldSendInitialPlatformDetails) {
       this.props.dispatch({
         type: updateLastCommunicatedPlatformDetailsActionType,
-        payload: { [this.props.urlPrefix]: getConfig().platformDetails },
+        payload: getConfig().platformDetails,
       });
     }
 
diff --git a/lib/types/device-types.js b/lib/types/device-types.js
--- a/lib/types/device-types.js
+++ b/lib/types/device-types.js
@@ -44,7 +44,3 @@
 export type VersionResponse = {
   +codeVersion: number,
 };
-
-export type LastCommunicatedPlatformDetails = {
-  +[urlPrefix: string]: PlatformDetails,
-};
diff --git a/lib/types/redux-types.js b/lib/types/redux-types.js
--- a/lib/types/redux-types.js
+++ b/lib/types/redux-types.js
@@ -17,10 +17,7 @@
   UpdateUserAvatarResponse,
 } from './avatar-types.js';
 import type { CryptoStore } from './crypto-types.js';
-import type {
-  VersionResponse,
-  LastCommunicatedPlatformDetails,
-} from './device-types.js';
+import type { VersionResponse, PlatformDetails } from './device-types.js';
 import type { ClientDBDraftInfo, DraftStore } from './draft-types.js';
 import type { EnabledApps, SupportedApps } from './enabled-apps.js';
 import type {
@@ -138,7 +135,7 @@
   +deviceToken: ?string,
   +commServicesAccessToken: ?string,
   +inviteLinksStore: InviteLinksStore,
-  +lastCommunicatedPlatformDetails: LastCommunicatedPlatformDetails,
+  +lastCommunicatedPlatformDetails: ?PlatformDetails,
   +keyserverStore: KeyserverStore,
   ...
 };
@@ -1160,7 +1157,7 @@
     }
   | {
       +type: 'UPDATE_LAST_COMMUNICATED_PLATFORM_DETAILS',
-      +payload: LastCommunicatedPlatformDetails,
+      +payload: PlatformDetails,
     }
   | { +type: 'RESET_USER_STATE', +payload?: void }
   | {
diff --git a/lib/utils/action-utils.js b/lib/utils/action-utils.js
--- a/lib/utils/action-utils.js
+++ b/lib/utils/action-utils.js
@@ -19,7 +19,7 @@
   type LogInStartingPayload,
   type LogInResult,
 } from '../types/account-types.js';
-import type { LastCommunicatedPlatformDetails } from '../types/device-types.js';
+import type { PlatformDetails } from '../types/device-types.js';
 import type { Endpoint, SocketAPIHandler } from '../types/endpoints.js';
 import type { LoadingOptions, LoadingInfo } from '../types/loading-types.js';
 import type {
@@ -373,7 +373,7 @@
   +sessionID: ?string,
   +currentUserInfo: ?CurrentUserInfo,
   +connectionStatus: ConnectionStatus,
-  +lastCommunicatedPlatformDetails: LastCommunicatedPlatformDetails,
+  +lastCommunicatedPlatformDetails: ?PlatformDetails,
 };
 
 // All server calls needs to include some information from the Redux state
@@ -403,7 +403,7 @@
       sessionID: ?string,
       currentUserInfo: ?CurrentUserInfo,
       connectionStatus: ConnectionStatus,
-      lastCommunicatedPlatformDetails: LastCommunicatedPlatformDetails,
+      lastCommunicatedPlatformDetails: ?PlatformDetails,
     ) => {
       const boundCallServerEndpoint = bindCookieAndUtilsIntoCallServerEndpoint({
         dispatch,
diff --git a/lib/utils/call-server-endpoint.js b/lib/utils/call-server-endpoint.js
--- a/lib/utils/call-server-endpoint.js
+++ b/lib/utils/call-server-endpoint.js
@@ -14,10 +14,7 @@
 import { updateLastCommunicatedPlatformDetailsActionType } from '../actions/device-actions.js';
 import { callServerEndpointTimeout } from '../shared/timeouts.js';
 import type { Shape } from '../types/core.js';
-import type {
-  PlatformDetails,
-  LastCommunicatedPlatformDetails,
-} from '../types/device-types.js';
+import type { PlatformDetails } from '../types/device-types.js';
 import {
   type Endpoint,
   type SocketAPIHandler,
@@ -95,7 +92,7 @@
   urlPrefix: string,
   sessionID: ?string,
   connectionStatus: ConnectionStatus,
-  lastCommunicatedPlatformDetails: ?LastCommunicatedPlatformDetails,
+  lastCommunicatedPlatformDetails: ?PlatformDetails,
   socketAPIHandler: ?SocketAPIHandler,
   endpoint: Endpoint,
   input: { [key: string]: mixed },
@@ -109,9 +106,7 @@
 
   const shouldSendPlatformDetails =
     lastCommunicatedPlatformDetails &&
-    !_isEqual(lastCommunicatedPlatformDetails[urlPrefix])(
-      getConfig().platformDetails,
-    );
+    !_isEqual(lastCommunicatedPlatformDetails)(getConfig().platformDetails);
 
   if (
     endpointIsSocketPreferred(endpoint) &&
@@ -227,9 +222,7 @@
   if (!error && shouldSendPlatformDetails) {
     dispatch({
       type: updateLastCommunicatedPlatformDetailsActionType,
-      payload: {
-        [urlPrefix]: getConfig().platformDetails,
-      },
+      payload: getConfig().platformDetails,
     });
   }
 
diff --git a/native/redux/redux-setup.js b/native/redux/redux-setup.js
--- a/native/redux/redux-setup.js
+++ b/native/redux/redux-setup.js
@@ -121,7 +121,7 @@
   inviteLinksStore: {
     links: {},
   },
-  lastCommunicatedPlatformDetails: {},
+  lastCommunicatedPlatformDetails: null,
   keyserverStore: {
     keyserverInfos: {
       [ashoatKeyserverID]: {
diff --git a/native/redux/state-types.js b/native/redux/state-types.js
--- a/native/redux/state-types.js
+++ b/native/redux/state-types.js
@@ -3,7 +3,7 @@
 import type { Orientations } from 'react-native-orientation-locker';
 import type { PersistState } from 'redux-persist/es/types.js';
 
-import type { LastCommunicatedPlatformDetails } from 'lib/types/device-types.js';
+import type { PlatformDetails } from 'lib/types/device-types.js';
 import type { DraftStore } from 'lib/types/draft-types.js';
 import type { EnabledApps } from 'lib/types/enabled-apps.js';
 import type { EntryStore, CalendarQuery } from 'lib/types/entry-types.js';
@@ -57,7 +57,7 @@
   +userPolicies: UserPolicies,
   +commServicesAccessToken: ?string,
   +inviteLinksStore: InviteLinksStore,
-  +lastCommunicatedPlatformDetails: LastCommunicatedPlatformDetails,
+  +lastCommunicatedPlatformDetails: ?PlatformDetails,
   +keyserverStore: KeyserverStore,
   +localSettings: LocalSettings,
 };
diff --git a/native/socket.react.js b/native/socket.react.js
--- a/native/socket.react.js
+++ b/native/socket.react.js
@@ -100,7 +100,7 @@
     }, [active, navContext]);
 
     const lastCommunicatedPlatformDetails = useSelector(
-      state => state.lastCommunicatedPlatformDetails[urlPrefix],
+      state => state.lastCommunicatedPlatformDetails,
     );
 
     const dispatch = useDispatch();
diff --git a/web/redux/redux-setup.js b/web/redux/redux-setup.js
--- a/web/redux/redux-setup.js
+++ b/web/redux/redux-setup.js
@@ -18,7 +18,7 @@
   OLMIdentityKeys,
   PickledOLMAccount,
 } from 'lib/types/crypto-types.js';
-import type { LastCommunicatedPlatformDetails } from 'lib/types/device-types.js';
+import type { PlatformDetails } from 'lib/types/device-types.js';
 import type { DraftStore } from 'lib/types/draft-types.js';
 import type { EnabledApps } from 'lib/types/enabled-apps.js';
 import type { EntryStore, CalendarQuery } from 'lib/types/entry-types.js';
@@ -95,7 +95,7 @@
   +_persist: ?PersistState,
   +commServicesAccessToken: ?string,
   +inviteLinksStore: InviteLinksStore,
-  +lastCommunicatedPlatformDetails: LastCommunicatedPlatformDetails,
+  +lastCommunicatedPlatformDetails: ?PlatformDetails,
   +keyserverStore: KeyserverStore,
 };
 
diff --git a/web/socket.react.js b/web/socket.react.js
--- a/web/socket.react.js
+++ b/web/socket.react.js
@@ -65,7 +65,7 @@
     const callLogOut = useServerCall(logOut);
 
     const lastCommunicatedPlatformDetails = useSelector(
-      state => state.lastCommunicatedPlatformDetails[urlPrefix],
+      state => state.lastCommunicatedPlatformDetails,
     );
 
     return (