idk just #thinking
lets call each nostr-filter shape we use a "channel"

per channel, lets declare "eose-plus" as undefined until real 'eose' arrive, then keeps set it to eose timestamp and adjust on latest "EVENT" received

each channel keeps <<pubkey | id>, eose-plus> map

when client requests an id, if its marked with an "eose-plus" then request '"since": <eose-plus>
append ids with similar eose-plus to for as less filters as possible IF they are still much compromise for full delivery

if current subscription isn't stable (no eose-plus) make a transitory subscription
when all subs are stable, merge to a single one with latest "since"

such setup suppose a service to control which ids to be forwarded or withdrawed