I wonder why surveying of areas outsides of cities need to be done atm? There are a few of these craft out today.

This is who fly the planes. They sound like pretty cool planes, essentially its civilian reconnaissance.
https://ravenair.co.uk/aerial-survey/ 

ooh, a third plane, over london.

and a 4th!

I wonder what the hell they are surveying, en mass, during the bank holiday weekend?!

OH, another one, this one is over great Yarmouth.
The owner of this plane is alot more mysterious, and could be government owned.

https://assets.publishing.service.gov.uk/media/5422ffdbe5274a13140009e1/dft_avsafety_pdf_500259.pdf

and another!
this last 2 are RVL group - ariel surveillance!

Big brother is watching!

And Another, it looks like it just got into position.

This one has a private owner.

If its any consolation, its only England which seems to have this seemingly large amount of surveillance aircraft flying around when nothing else is, and people are being told to stay indoors.

This shows the paths the above planes have taken yesterday + today (as they are flying now).

It's like they are trying to record most of England. As pointed out, they dont seem to be following anything specific, just scanning areas.

Is this the UK's #Coronavirus Surveillance?

Who knows, maybe they are using the empty streets to get a load of high-quality imagery for google maps although it raises the question of "that be 'key work'?", which I doubt it would be, so ye, I wonder what they are doing.