On UA 924 tonight IAD-LHR at 11pm. Booked J/business ticket thru travel agent on Friday; manually requested a GPU upgrade on website Friday; shown as wait listed till sun pm..
Swing by the airport this am ( I had other business + had read about disappearing upgrade requests). Agent at GS counter : " we have no record of your upgrade request" [ I am now within T-24 window]...
Ok, she is very nice, puts me in manually, but unable to explain upgrade policy ("I am seeing premiers clear before GS, I have no idea what's happening").
Get home, call the GS line, ask "what's happening?". After 10 min hold, she tells me "some agent in Detroit deleted the whole waitlist...."
Does anyone know what the upgrade policy really is? Are these issues IT issues? Or is it new policy that at T-24 (a) existing waitlists are trashed (b) upgrades are then given by fare trumping status?

Been a heavy GS since the program begun, very confused now as to what's happening.