Originally Posted by
te36
But so.. what could this dark matter be that fills up these seats so late, and without showing up in the upgrade list - is there some other place i could look at to diagnose where it comes from ? I wanted to ask at the gate but they where so horrible busy and i didn't want to be left at the airport alone after i finally got the upgrade and they where about to close the door ;-)
People that had not selected a seat until check-in at the airport and yes this does happen.
People making cash purchased of the upgrade
People SDCing on to the flight
People whose flight plans have been disrupted by irrops
People making last minute ticket purchases
None of the above is unusual or rare and can happen on most flights.
All of the above are reasons UA does not process all the upgrades long before departure.
The seatmap is a poor indicator of the true status. Look (with expert mode) what the J inventory is. Or look just above the waitlist on united.com or app and what the sold seat counts are.