Unfortunately NWA and others have hidden the "R" bucket... I typically look for flights that show more than F6 before booking. Below that # the "R" bucket does not appear to be available for early upgrades. Ocasionally though, if it still shows more than F4 a couple of days out I have received upgrades.

The "P" bucket does not appear to have as big of an effect as the "F" bucket though. While it is still a pain and causes much mental turmoil, the EUA for me, has still been available at the gate... My only misses this year were earlier this year before the bankruptcy filing, so I still think the system works, just not well as we have come to expect, or like.

For example I am traveling from ATL-DTW-LAN on Thursday and the ATL-DTW leg has cleared but the DTW-LAN leg has not. KVS still shows P3 F3, so I expect to get upgraded at the gate. If I don't I'll be happy to get the 1K bonus.