diff --git a/synapse/storage/databases/main/delayed_events.py b/synapse/storage/databases/main/delayed_events.py
index 8b631463c8d..ef4921d77ab 100644
--- a/synapse/storage/databases/main/delayed_events.py
+++ b/synapse/storage/databases/main/delayed_events.py
@@ -53,7 +53,7 @@
 Delay = NewType("Delay", int)
 Timestamp = NewType("Timestamp", int)
 
-DelayedEventDetails = Tuple[
+DelayedPartialEvent = Tuple[
     RoomID,
     EventType,
     Optional[StateKey],
@@ -295,7 +295,7 @@ async def get_all_for_user(
         ]
 
     async def process_all_delays(self, current_ts: Timestamp) -> Tuple[
-        List[DelayedEventDetails],
+        List[DelayedPartialEvent],
         List[Tuple[DelayID, UserLocalpart, Delay]],
     ]:
         """
@@ -305,10 +305,10 @@ async def process_all_delays(self, current_ts: Timestamp) -> Tuple[
         """
 
         def process_all_delays_txn(txn: LoggingTransaction) -> Tuple[
-            List[DelayedEventDetails],
+            List[DelayedPartialEvent],
             List[Tuple[DelayID, UserLocalpart, Delay]],
         ]:
-            events: List[DelayedEventDetails] = []
+            events: List[DelayedPartialEvent] = []
             removed_timeout_delay_ids: Set[DelayID] = set()
 
             txn.execute(
@@ -359,7 +359,7 @@ async def pop_event(
         delay_id: DelayID,
         user_localpart: UserLocalpart,
     ) -> Tuple[
-        DelayedEventDetails,
+        DelayedPartialEvent,
         Set[DelayID],
     ]:
         """
@@ -388,7 +388,7 @@ def _pop_event_txn(
         txn: LoggingTransaction,
         keyvalues: Dict[str, Any],
     ) -> Tuple[
-        DelayedEventDetails,
+        DelayedPartialEvent,
         Set[DelayID],
     ]:
         row = self.db_pool.simple_select_one_txn(
@@ -422,7 +422,6 @@ def _pop_event_txn(
             txn,
             keyvalues={"delay_rowid": parent_rowid or target_delay_rowid},
             retcols=("delay_id",),
-            allow_none=False,
         )
 
         contents: JsonDict = db_to_json(event_row[4])
@@ -461,7 +460,6 @@ async def remove(
                 "user_localpart": user_localpart,
             },
             retcols=("delay_id",),
-            allow_none=False,
         )
         return {DelayID(r[0]) for r in removed_timeout_delay_ids}
 
@@ -494,7 +492,7 @@ def _remove_txn(
         txn: LoggingTransaction,
         keyvalues: Dict[str, Any],
         retcols: StrCollection,
-        allow_none: bool,
+        allow_none: bool = False,
     ) -> List[Tuple]:
         """
         Removes delayed events matching the keyvalues, and any children they may have.
@@ -503,7 +501,7 @@ def _remove_txn(
             The specified columns for each delayed event with a timeout that was removed.
 
         Raises:
-            NotFoundError if allow_none is True and no delayed events match the keyvalues.
+            NotFoundError if allow_none is False and no delayed events match the keyvalues.
         """
         sql_with = f"""
             WITH target_rowids AS (