It will only show a booking that contains BA flights, and then may not show all of it.

I recently booked a US return with connections with AA, where the return transatlantic segment was a BA flight. The result was that the BA site showed my US->UK trip (including AA segments), but didn't show the UK->US half at all. Kind of weird but I can see the logic.

Wish they'd just show the whole thing really, but I wouldn't want to be the guy in charge of that IT project.