Originally Posted by
COYG
I just checked at T-120. If I'm able to be upgraded, the F seats should be open to choose for free. The 'you've been upgraded' email will arrive a few hours later.
It will process it automatically a few mins later as well. Sounds like you happened to check your reservation after the space opened up but just before the auto sweep run in which case you were able to process the upgrade in seat-map yourself for free.