Sorry to keep asking questions, but I am confused as to how the upgrade availability relates to fare buckets. A couple of questions:
1. if RN availability for a flight is greater than 0, why does upgrading with miles show "waitlist only"?
2. If "waitlist" only is shown, but the corresponding bucket has availability, will the upgrade clear immediately afterwards, or do I still wait until my window (day of departure) for clearance?
3. BONUS: is "day of departure" the same as 24hrs in advance?
Thanks in advance