Can someone explain how on earth this scenario is possible:
I am Platinum:

Booked a ticket for 11/7 departure on 11/4; there were no C+ seats available at the time of booking, so C+ didn't clear shortly after, but it did clear C+ about 36 hours prior to departure.
With ~16hr before departure, I am looking at about 44 people on the First Class upgrade list I am 18th, but the majority of the ppl ahead of me are also on the C+ upgrade list as well. How did I clear C+ before them but yet be a lower priority on the First Class upgrade?

ps. I think 44 people on the First Class upgrade list is the record I've seen. It's an SNA - ATL flight.