Originally Posted by
Wasabi Tofu
Edit:
Asismiles permit roundtrip upgrade from D class to First on BA and AA but not for oneway.
This is a tricky part for upgrade of RTW.
I have no real experience, but theoretically, Asiamiles permit upgrade for AA/BA's roundtrip flights within a RTW.
But I believe open-jaw (so something like HKG-(BA)-LHR-(BA)-LAX) is allowed, right?