There is very little airport sit. Mostly at the beginning of the day you will be put on Airport standby to cover the time after checkout until your first flight. If your first flight isn't until 5 or 6 PM then instead of airport standby they will pay for a 2 night stay, even though you only spent one night. As for afternoon airport standby that is also rare (but more often) but it wiil only be for an hour or 2 as it will be to cover another plane in the area until they get airborne. Normall there is very little airport sit time.