Usually they show as “closed” right away if the agent uses the easy-button method to apply them and they clear, or if you self-apply them online and they clear. In this case the tickets usually just revalidate instead of needing to be reissued.

Sometimes they still show “open” if an agent applies them the old school way and a ticket issue is required, but it hasn’t been reissued yet. This is where online checkin fails and you have to call in and get things reissued.

They only time they should only stay open all the way until after a flight where they close is a waitlisted upgrade that clears at the gate (with no other cleared segments on that same certificate.) Once in a while you’ll get lucky on this in that the certificate never gets closed.

Lastly, even if a reservation is cancelled the RUC will stay closed and you will have to call in and get it reopened if you wish to attempt to reuse it.