Yes, it is frustrating, but as pointed many times before it is something to take up with CX. It is CX that single out BAEC members and do not want to pay BA for earnings with P class. It does make no sense given that P is not the lowest class, but who knows what logic (if any) CX follows. They may simply be happy that BAEC members are flying with CX without CX having to pay BAEC for it.