IAH to PHX on Oct24...
I was watching the flight since an EUA hadn't come thru (Plat). Was booked 4 out of 20 seats so thot it was a little odd that they'd be holding back so many seats for sale. Particularly since the number of days till departure kept getting closer and closer with no change in the F bookings (nor re-allocate a few more seats to the EUA bucket).
This was the return portion of my trip. When I checked in for the outbound, I selected the "auto check-in" function for the return. When I woke up that morning I had my e-boarding pass on my smart phone and I had been upgraded.
I came to the self conclusion (which has been mentioned here) that they must be doing a lot of program updates and/or conversions to get rid of SkyTeam and introduce :-:A. That EUA was probably a low priority program so might be turned off except for the "24 hour" run.
Bottom line: while I didn't have the luxury of being upgraded until day of departure, the upgrades appeared to be run in order with no battlefield issues.
Steve