Confused on the information I'm seeing. LHR-BNA on flight aware shows the 772 as the aircraft flying recently, which from what I can tell isn't a valid seat layout per aerolopa (historical seat map section). The seat map for the flight on 9/28 indicates the B77L and it was reported a few months ago, this would be the jet they use for this route.

Any ideas which is correct, the seat map or flight aware? Is the 772 still being used in general?