I'm a 1K this year (1P next) and I have had horrible success. The past 3 out of 4 failed to clear and probably more like 5 out 7 have filed to clear. Granted much of this is booked a few days in advance but still it really sucks. I booked a flight SFO LHR 7 weeks in advance and the upgrades didn't clear right away. The alternative was to fly through ORD and then a 7 hour lay over in LHR. No thanks. Now 3 weeks in advance, they cleared. Basically there is zero upgrade availability. Consider your success being very lucky.