Originally Posted by ExAAerOnDL

As to the first question, it doesn't really. In all likelihood, the GA will upgrade Medallions and full fare passengers to make room in coach for oversales. So after they clear the upgrade list, they'll look for the high value passengers.

As to the second question, the seat map is horribly unreliable. Looking at your example, your odds of an op-up are basically zero. Premium cabin (J/D/S/I) is zeroed out in all inventories, so it's full. Looking at the Economy cabin (Y and below), that tells me that there are at least 7 seats available (Y7), but not many more (since B/M are down to 5). I would guess 7-10 seats in coach.

Finally, some people just don't choose a seat assignment, or their online profile says they want an aisle seat and there are none available - so they just end up with nothing. In the end, opting against a seat assignment is a risky game of middle-seat roulette.

Caveat - this is based on my knowledge as an AA employee. DL may handle things differently.