I noticed that the BA 777 flight from Shanghai to Heathrow came up on Flighttracker24 earlier today, with a General Emergency squawk code. Probably after the event with the sonic boom, but the same squawk was used by the aircraft that went back to Glasgow earlier in the week. I wonder if restrictions on "making booms" is lifted for a scramble in such situations. I would imagine the thought that he could legally do the business would make life on Q a bit more interesting for the pilots. I've seen nothing on TV re the BA bird, so assume it was some sort of precautionary, or possibly an accidental transmission.
The report of trees breaking apart seems a bit heavy for a sonic boom, windows broken yes, but trees?
Smudge