It’s been circulating for a while now, holding just below 11,000 feet

Title says it all- just wondering as it seems rare to see this many 7700s at once. Is there an issue specific to London?
Flights are:

BA2607 (diverted to stansted, landed, fire trucks on runway)

BY4249 (diverted to stansted, landed, fire trucks on runway)

BA2703 (diverted to stansted, landed, fire trucks on runway)

U28186 (diverted to Luton, landed)

U28012 (diverted to Luton, landed)

U28042 (diverted to Luton, landed)

BA2591 (diverted to Stansted initially but has now landed at Gatwick. Fire trucks on runway)

U28704 (diverted to Luton, landed)

LS3104 (diverted to Stansted, landed, fire trucks on runway)

U28330 (diverted to Stansted, landed, fire trucks on runway)

(Just in the time of writing this post it’s gone from 6 to 8)

Update - now 10 total but have updated to list which ones have landed. Can’t change the title of the post unfortunately but will update with registrations if any more pop up.

Update 2- all have now landed and Gatwick appears to be reopen for arrivals.