I hit PM earlier this year and chose the RUCs, a couple of data points, if it helps:
1st use, ATL-SMF & SMF-ATL, wait-listed on both a few days out, mid-week flights, both cleared at gate.
2nd use, attempted to use RUC ATL-SMF at T-20ish since the upgrade list showed me at number 16, Mon AM dept, once applied, I was number 6 for 1, didn't get it.
3rd use, SMF-ATL (yesterday); applied at T-12 when I saw I was number 6 for 2, after applying, went to 1 for 2, ended up getting it.
Best regards,