RDU-ATL - Sunday, September 13 - successful - gate agent upgraded without request, flight (including BC) full
ATL-FNT - Tuesday, September 22 - successful - submitted request to gate agent 40 mins prior - seats throughout (including BC) vacant
FNT-ATL - Wednesday, September 23 - unsuccessful - flew standby and was fortunate to get a coach seat, much less BC
ATL-FNT - Monday, October 5 - unsuccessful - submitted request to gate agent 40 mins prior and was told all the upgrades had already been given out, BC was full but main cabin was about 60% capacity, ended up in an exit row with a vacant seat next to me
FNT-ATL - Friday, October 9 - successful - flew standby and was also able to get upgraded about 1 hour prior to boarding. BC was full but the main cabin looked to be less than 50%

I'll be back on the ATL-FNT-ATL next week and I'll let you know what happens there. But I share in the frustration over when you should request the upgrade, particularly after getting beaten out on October 5th. I called the A+ Elite line and the agent told me to approach the gate agent ASAP and that the list is not limited to 40-minutes prior to boarding, despite what I've read on the FL website. Seems that will be my MO from now on. All in all, I've been pretty satisfied with the program.