diff --git a/synapse/appservice/scheduler.py b/synapse/appservice/scheduler.py
index 185e3a5278..598167c4af 100644
--- a/synapse/appservice/scheduler.py
+++ b/synapse/appservice/scheduler.py
@@ -103,7 +103,7 @@ class ApplicationServiceScheduler:
         self.queuer.enqueue_event(service, event)
 
     def submit_ephemeral_events_for_as(
-        self, service: ApplicationService, events: List[JsonDict]
+        self, service: ApplicationService, events: Iterable[JsonDict]
     ) -> None:
         self.queuer.enqueue_ephemeral(service, events)
 
@@ -141,7 +141,7 @@ class _ServiceQueuer:
         self._start_background_request(service)
 
     def enqueue_ephemeral(
-        self, service: ApplicationService, events: List[JsonDict]
+        self, service: ApplicationService, events: Iterable[JsonDict]
     ) -> None:
         self.queued_ephemeral.setdefault(service.id, []).extend(events)
         self._start_background_request(service)
diff --git a/synapse/handlers/appservice.py b/synapse/handlers/appservice.py
index fb9ad3ba62..1b08ded9fe 100644
--- a/synapse/handlers/appservice.py
+++ b/synapse/handlers/appservice.py
@@ -325,7 +325,7 @@ class ApplicationServicesHandler:
                         )
 
                     elif stream_key == "to_device_key":
-                        # Retrieve an iterable of to-device message events, as well as the
+                        # Retrieve a list of to-device message events, as well as the
                         # maximum stream token of the messages we were able to retrieve.
                         events = await self._handle_to_device(service, new_token, users)
                         if events: