Thanks all for the comments and yes i did indeed ask on BA forum (clearly violating cross posting rules
but i hope this thread stays open as the topic seems rather useful for AS fliers)
Originally Posted by
Erasmus
I have not (yet) credited BA flights upgraded with Avios to AS, but have always credited such flights to AA in the past with no issue. The trick with Avios is they can only upgrade their own ticket stock, so make sure BA issues the ticket!
Thanks! So you booked with your BA#, confirmed upgrade and then called BA to change FF# to AA? Or was it booked with AA# from the beginning and BA could apply avios upgrade to such reservation?