Google was right....
G-BOAB has been moved around LHR repeatedly, and she was indeed parked for some time inside the old "detuner" (engine run-up silencer), which is what that recent "what's this then" post and picture are all about.
It's a pity, really.... All the other British Concordes have found a "home" one way or another (except G-BOAF, maybe,, but let's not go into that for the moment), and G-BOAB is slowly becoming the "forgotten" Concorde.
CJ