On AA's site it says this (from post #2).
What order are upgrades confirmed?
As soon as your upgrade window opens, we'll attempt to confirm your upgrade.
If an upgrade is available, we'll confirm it before departure based on your elite status level and the order it was received
Fares booked in Y and B are confirmed within each status level first, followed by all other fares.
If your upgrade was auto-requested, you'll be added to the upgrade list within minutes of making your reservation and your request date and time will be the date and time the upgrade was added to your reservation.
"Fares booked in Y and B are confirmed within each status level first, followed by all other fares."
So who is correct?