When creating a session store from the DSL, and you get a ReadOnlySessionStore, you can fetch by key, but not by key and time as in a SessionStore, even if the key type is a Windowed<K>. So you would have to iterate through it to find the time-related entries, which should be less efficient than querying by time.
So the purpose of this ticket is to be able to query the store with (key, time).
Proposal is to add SessionStore's findSessions-like methods (i.e. time-bound access) to ReadOnlySessionStore.