My experience the past month (about 12 segments) is that EUA has been running a little late - maybe more like 3-4 minutes after the EUA time - not right at EUA. So if you checked at 5:02, just 2 minutes after EUA time, EUA may not have run - so the "F" bucket was still open and EUA had not run.

Did you check at say 5:05? 5 minutes after. I suspect that EUA did run and you did not make the cut and that "F" was then zero. "F" can reopen, but usually not at 2 minutes after - usually a few hours at least.

The same thing has happened to me. I checked at 1 minute after, then 2 minutes after, and I thought I missed the upgrade as F still showed. A few minutes later about 3-5 minutes after that EUA time I checked and had gotten the upgrade. If I missed the upgrade it was because they only had 1 or 2 "F" seats and I did not make the cut.

Best thing to do is check "F" before EUA, continue to check with more passengers to determine the number of "F" seats, print out the F and Y seat maps before EUA, then wait at least 5 minutes after EUA time. Check "F" availability and seat maps. I believe you will see that everything is OK - that the number of people moved up.

If is within your EUA time and you did not make then cut, I bet you will see "F" at zero 5 minutes after EUA time.

The system seems to be working . I suspect they delayed EUA a few minutes to allow autocheckin to clear, etc.