diff --git a/maubot/client.py b/maubot/client.py
index b0fde73..5c98498 100644
--- a/maubot/client.py
+++ b/maubot/client.py
@@ -372,7 +372,10 @@ class Client(DBClient):
         _, server = self.client.parse_user_id(evt.sender)
         room_id = await self.client.join_room(evt.content.replacement_room, servers=[server])
         power_levels = await self.client.get_state_event(room_id, EventType.ROOM_POWER_LEVELS)
-        if power_levels.get_user_level(evt.sender) < power_levels.invite:
+        create_event = await self.client.get_state_event(
+            room_id, EventType.ROOM_CREATE, format="event"
+        )
+        if power_levels.get_user_level(evt.sender, create_event) < power_levels.invite:
             self.log.warning(
                 f"{evt.room_id} was tombstoned into {room_id} by {evt.sender},"
                 " but the sender doesn't have invite power levels, leaving..."
diff --git a/requirements.txt b/requirements.txt
index e1df001..ff09981 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-mautrix>=0.20.7,<0.21
+mautrix>=0.20.9rc2,<0.21
 aiohttp>=3,<4
 yarl>=1,<2
 asyncpg>=0.20,<1