Was the flight full? Sounds like the GA was pressed for time and found out about the no-shows right at departure time, and the non-revs got on at last minute and was told to take the empty 1st class seats to get the flight out on time. Not saying it's right or wrong. Just speculating. But if all the eligible upgrades boarded, do they forfeit their upgrade opportunity or is the GA suppose to come on and upgrade the next on the list? It seems like I've seen both done, so I never know what the actually policy is. I do know that the GA wants the door closed on time so a delay is not blamed on them.