diff --git a/lib/api/marianumconnect/auth/auth_interceptor.dart b/lib/api/marianumconnect/auth/auth_interceptor.dart
index cc301e9..b78ac97 100644
--- a/lib/api/marianumconnect/auth/auth_interceptor.dart
+++ b/lib/api/marianumconnect/auth/auth_interceptor.dart
@@ -36,7 +36,15 @@ class MarianumConnectAuthInterceptor extends Interceptor {
     // Token mitschicken statt ein eigenes 401 einzufangen.
     final pending = _pendingReLogin;
     if (pending != null) await pending;
-    final token = await _tokenStorage.readToken();
+    // Reading the keystore can throw while the device is locked (iOS
+    // errSecInteractionNotAllowed on background requests). Degrade to an
+    // unauthenticated request instead of surfacing a platform error.
+    String? token;
+    try {
+      token = await _tokenStorage.readToken();
+    } catch (_) {
+      token = null;
+    }
     if (token != null && token.isNotEmpty) {
       options.headers['Authorization'] = 'Bearer $token';
     }
diff --git a/lib/api/marianumconnect/auth/token_storage.dart b/lib/api/marianumconnect/auth/token_storage.dart
index f5f00e8..1e19f64 100644
--- a/lib/api/marianumconnect/auth/token_storage.dart
+++ b/lib/api/marianumconnect/auth/token_storage.dart
@@ -1,5 +1,13 @@
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 
+/// `first_unlock` accessibility so the token can be read during background
+/// requests (telemetry heartbeat, push-triggered syncs) after the first device
+/// unlock following a reboot. The keychain default (`whenUnlocked`) throws
+/// `-25308 errSecInteractionNotAllowed` when the device is locked.
+const IOSOptions _mcIosOptions = IOSOptions(
+  accessibility: KeychainAccessibility.first_unlock,
+);
+
 /// Persists the Marianum-Connect bearer token in the platform keystore. Kept
 /// separate from `AccountData` because the username/password live on (Nextcloud
 /// + MHSL still need them) while the MC token is short-lived and per-endpoint.
@@ -11,7 +19,7 @@ class MarianumConnectTokenStorage {
   final FlutterSecureStorage _storage;
 
   const MarianumConnectTokenStorage([
-    this._storage = const FlutterSecureStorage(),
+    this._storage = const FlutterSecureStorage(iOptions: _mcIosOptions),
   ]);
 
   Future<String?> readToken() => _storage.read(key: _tokenKey);
diff --git a/lib/main.dart b/lib/main.dart
index a1641c7..ee2880c 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -121,10 +121,19 @@ Future<void> main() async {
     ),
   );
 
+  // Diagnostic log only. getToken() can fail transiently during cold start
+  // (Android: "IOException: FCM Registration failed!" from Play Services,
+  // iOS: apns-token-not-set until APNS registration completes), so tolerate
+  // the failure instead of letting it surface as an uncaught async error that
+  // gets reported to the telemetry backend as noise.
   unawaited(
-    FirebaseMessaging.instance.getToken().then(
-      (token) => log('Firebase token: ${token ?? "Error: no Firebase token!"}'),
-    ),
+    FirebaseMessaging.instance
+        .getToken()
+        .then(
+          (token) =>
+              log('Firebase token: ${token ?? "Error: no Firebase token!"}'),
+        )
+        .onError((e, _) => log('Firebase token unavailable: $e')),
   );
 
   // Warm up the Nextcloud root listing in the background while the user is
diff --git a/lib/model/account_data.dart b/lib/model/account_data.dart
index 8ba8a3a..3172a91 100644
--- a/lib/model/account_data.dart
+++ b/lib/model/account_data.dart
@@ -2,7 +2,6 @@ import 'dart:async';
 import 'dart:convert';
 
 import 'package:crypto/crypto.dart';
-import 'package:firebase_messaging/firebase_messaging.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
@@ -57,14 +56,6 @@ class AccountData {
       .convert(utf8.encode('${getUsername()}:${getPassword()}'))
       .toString();
 
-  Future<String> getDeviceId() async => sha512
-      .convert(
-        utf8.encode(
-          '${getUserSecret()}@${await FirebaseMessaging.instance.getToken()}',
-        ),
-      )
-      .toString();
-
   Future<void> setData(String username, String password) async {
     await _secureStorage.write(key: _usernameField, value: username);
     await _secureStorage.write(key: _passwordField, value: password);
diff --git a/lib/model/data_cleaner.dart b/lib/model/data_cleaner.dart
index ed88004..925980c 100644
--- a/lib/model/data_cleaner.dart
+++ b/lib/model/data_cleaner.dart
@@ -9,7 +9,7 @@ class DataCleaner {
         .get();
     cacheData?.forEach((key, value) async {
       final lastUpdate = DateTime.fromMillisecondsSinceEpoch(
-        value['lastupdate'] as int,
+        ((value['lastupdate'] as num?) ?? 0).toInt(),
       );
       if (DateTime.now()
           .subtract(const Duration(days: 200))
diff --git a/lib/state/app/infrastructure/loadable_state/bloc/loadable_state_bloc.dart b/lib/state/app/infrastructure/loadable_state/bloc/loadable_state_bloc.dart
index edcdeda..9c07d3b 100644
--- a/lib/state/app/infrastructure/loadable_state/bloc/loadable_state_bloc.dart
+++ b/lib/state/app/infrastructure/loadable_state/bloc/loadable_state_bloc.dart
@@ -27,8 +27,12 @@ class LoadableStateBloc extends Bloc<LoadableStateEvent, LoadableStateState>
       }
     });
 
-    void emitConnectivity(List<ConnectivityResult> result) =>
-        add(ConnectivityChanged(LoadableStateState(connections: result)));
+    void emitConnectivity(List<ConnectivityResult> result) {
+      // The initial checkConnectivity() future is not cancellable and may
+      // resolve after the bloc was disposed, so guard against a closed sink.
+      if (isClosed) return;
+      add(ConnectivityChanged(LoadableStateState(connections: result)));
+    }
 
     Connectivity().checkConnectivity().then(emitConnectivity);
     _updateStream = Connectivity().onConnectivityChanged.listen(
@@ -48,10 +52,10 @@ class LoadableStateBloc extends Bloc<LoadableStateEvent, LoadableStateState>
     // Re-check connectivity so the resulting [ConnectivityChanged] handler
     // clears a stale error bar and triggers [reFetch] once reachable again.
     unawaited(
-      Connectivity().checkConnectivity().then(
-        (result) =>
-            add(ConnectivityChanged(LoadableStateState(connections: result))),
-      ),
+      Connectivity().checkConnectivity().then((result) {
+        if (isClosed) return;
+        add(ConnectivityChanged(LoadableStateState(connections: result)));
+      }),
     );
   }