Thanks. I am about to book using miles in F AA from SFO to LAX CX from LAX to HKG side trip to SGN ticketed separately on CX CX from HKG to BKK CX from BKK to SFO via HKG.

My ? After ticketing can I change from routing to take CX direct from SFO to HKG if it becomes available? Would I need to do a ticket exchange? Please advise. Thanks