Removing an instance does not remove posts from Everything > Subscribed

I don't know if this is my understanding or an issue.

My main account is .world.

I subscribed to an instance that is federated, and have since unsubscribed and removed the instance and associated account from my Liftoff Accounts by long pressing and selecting delete.

Posts from the instance still appear in Everything > Subscribed. Is this working as designed or a bug?

Thanks!