Originally Posted by MIKEM

Agreed that the day of the week has an impact. However, from September to Christmas Thur, Fri, Sat, Sun, were not good. Prior to September the upgrades from SFo-PVG-SFO were better, but not now. It does not matter who has 100% upgrade record for 2010 on this route. The fact is if you have an upgradable Y fare now and want to use a SWU you have a 35% chance of clearing the one direct flight per day.