I used to be on SFO-NRT and return monthly, usually out on saturday or sunday and back on friday or saturday, and only got upgraded half the time I tried (3 of 6). 1 of 2 LAX-NRT. SFO-HKG has always been impossible for me but it sounds like it may be getting better. Last flight, ex-HKG, I was on a pricey ticket (well above W but I can't remember the fare class) and think I was 20th on the UG list when the plane left. Congrats on your good luck!