Originally Posted by
SeattleDavid
I knew it wouldn't be simple! But the essence is similar to upgrading BA metal, AA flight number, I guess - they need to change it to a prime flight number first, and that depends on who 'owns' or can access the ticket. And presumably one shouldn't assume that a B fare on the BA# will translate to a B fare on the prime AA#.
I'll just start by asking our corporate travel agent if they can book it as an AA flight number to begin with and still get the great price I was seeing – as part of a BA Premium Economy trip from SFO-LHR and returning from Manchester.
When you want to upgrade a codeshare flight, the rules for the marketing carrier apply. While B can be upgraded as an AA prime flight, it cannot be upgraded as a BA*AA flight. If you want to upgrade a BA*AA flight with AA miles then the flight must be booked in
Y class. It does not matter what the booking code will map into on AA; the re-booking onto the operating carrier happens because the upgrade booking classes only exist on the operating carrier. Even though it has not been confirmed officially, I tend to believe that the ticket must be issued by AA/on AA stock in order to process an upgrade. I don't think AA will do anything with 125 stock.
If you want to travel to a joint business destination then it is possible to book the domestic flight as AA prime flight, however, if the underlying fare is
T the flight will book into
H on AA.