Originally Posted by
1Aturnleft
From the options you've shared then AA would be my preference but I'd book them as BA codeshare flight numbers in order to have their book with confidence features associated with the booking.
I hate to be the boring pedant, but for clarity someone has to be. It’s the
ticketing carrier that determines BWC (and similar) flexibility. Flight numbers - marketed, operated, codeshare or intergalactic, are irrelevant. AA could book under the BA code and you’d still have the AA conditions if it’s on 001 paper.
FWIW, with a group such as the OP’s, I’d be looking to depart LHR on VS/DL metal, purely because the Clubhouse would be a fantastic experience to share. Assuming prices are similar, of course.