Won't let me purchase seats in advance I am trying to book a round trip from IAD to BOM in November with a connection in LHR each way. All flight segments are on BA. The BA website allows me to purchase a seat for the LHR - BOM and BOM-LHR legs, but not for the IAD-LHR and LHR-IAD legs....
https://www.flyertalk.com/foru....m/british-airways-br