Originally Posted by Wilbur
TiteG4 - I think that MillionMiler's reasoning is correct, although in application it seems spotty.
I have only AA status, so I guess I am getting lucky.
YVR-HKG seems to happen because they filled the J seats in New York, and so they bump me up to first.
ICN-TPE just because they like my face - the airplane wasn't full.
LAX-HKG appears to be because J is full.
There is no exact science to Op Ups on any airline. As for CX though, I'm OW Emerald and on one of the the LAX-HKG flights on a certain night of the week I've had 7 out of 8 flights upgraded from J to F over the last 18 months. I never asked for one and most came at the gate as I was boarding the plane.