Old Jan 25, 18, 9:18 am
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Join Date: Apr 2001
Location: NYC
Posts: 24,295
The F cabin can be filled with employees/non-revs, but as they're standing by for the flight in general, it's not like they'll be vacating any J seats, so it doesn't help with a Y-to-J upgrade.

They stop selling tickets at T-45m, which I believe is the ticketing (and check-in) cut-off. That's typically around when the gate agent will begin clearing the upgrade standby list into empty seats. The automated system used to clear upgrades until T-4 hours, (and then nothing until the gate) but I'm not entirely sure if that's still the case.
ijgordon is offline