On a recent flight from LAS-PHL, I was not upgraded at the 7-day window. Looked online a couple of days before the flight and saw F1. Checked in online about 20 hours prior to the flight. I was the only one upgraded at the gate.

When I was upgraded, the gate agent asked me when I checked in and how. Told him I used web check in and he smiled and said that he's noticing more and more people do this in order to snag the upgrade if they are not upgraded at the 7/3/1 window. Good story, eh?

And one more thing...when I checked in online, I did not have a printer handy, but I did it anyway. When I got to the airport, I had to get an actual pass. This did not impact my check-in time.