@Mods - this is a pseudo-crosspost from the BAEC forum, if you feel it violates TOS, please delete that one (I posted it 45 minutes ago and it doesn't seem to be soliciting a response).

I have an itinerary booked tomorrow (7/30) through AA that includes BUR-DFW on AA, and DFW-LHR on BA 192 (AA codeshare), all in economy. I have checked in for both flights on AA.com. When I printed my boarding pass on AA.com, my BA 192 BP lists seat 42K, though AA.com lists "Unassigned" for my seat in My Reservations. Neither AA nor BA phone agents are able to verify this seat assignment. I called BA, and I'm told that the "seat map is not available for your flight, please request a seat at check-in." In other words they can neither confirm nor deny that I have a seat.

Should I sleep OK tonight knowing that I have 42K actually assigned, or should I worry that I'm going to arrive in DFW and find out that I have no seat assignment?