Sorry to revive this thread and be tangential, but I was curious if someone could shed some light on at what time the airline will stop selling seats and make them available for upgrade? I.E. on my upcoming flight, I am on the standby list for a mileage upgrade from a low-fare coach ticket to Business. There is one business class seat available for purchase, and six first class seats available for purchase, per AA.com. At some point, I assume the Business -> First upgrades will clear, potentially opening up business seats that could allow my upgrade to clear. Am I right in that logic, and if so, how far in advance does this usually occur?