Originally Posted by irishguy28

Indeed, but BA is not a travel agent that will sell all possible tickets - even on a "partner" - and it naturally prefers to sell revenue tickets for its own services, rather than offering you BA flightcodes (or EI prime flights) on routes such as that. The same is true for all airlines; you won't be offered any LHR-USA with BA on the EI website when looking for revenue bookings; instead, they'll offer you connecting flights via DUB (admittedly, occasionally they offer a BA-operated LHR-DUB flight as part of an itinerary) and SNN rather than putting you on their "partners" BA and AA who have non-stop flights.