The GAR form doesn’t capture any health information about those on board. The NOTAM specifically requires an ICAO GenDec which you as PIC certify that nobody onboard is coming back with sickness symptoms
I phoned up Border Force a week or two ago and they told me they need just the GAR, adding that the quarantine implementation was not their department.
So this new stuff is either very new (perhaps post-quarantine i.e. 10th July on) or they didn’t know about it either.
The GAR is 100% enforced IME i.e. if you don’t file it, they will come and meet you.
The GENDEC is what Greece uses all the time, and you certify that you or your passengers do not have TB (tuberculosis, not a TB20) 
GENDEC and health declaration by PIC are applicable as per ICAO even pre-COVID but no one does them in the UK AFAIK, but maybe the NOTAMS now enforces to have one at hand AND to email to the health cell at Heathrow? in any case it is easier to generate one in Carl’s website…
Yes if you fly to some places you need as much prints as the number of employee in an international airport, they may even ask you to rewrite them on various coloured papers as every department use a specific colour or give you a new template
I’m sure the border force don’t care about the Gendec but having called the telephone number in the NOTAM for PHE (+44 (0)2087457209 ) they categorically told me that I need to send them an ICAO Gendec up to 45 minutes after landing in the UK as per this recent process.
Scilly Isles EGHE are now open as normal but no day trips allowed. The PPR form on their website asks the name of the establishment where you are staying. Well, there are about 3 and one of them is £500/night
Have you tried just putting N/A, day trip on the PPR form?
They specifically told me when I phoned up. No day trips allowed.
My guess is that they want an address of where you are staying, so they can lock it down if you later tested positive. But due to the layout of the airport and the entrance gate, it is obvious that you could just put down any old hotel name on the form and go wild camping, which would be the safest thing anyway
BTW the usual email for EGHE does not work so they won’t get the PPR form
You have to use a temp email 
Just been doing the docs posted above, for a day trip to LFAT.
I estimate the time taken about 10 mins, plus 10 mins for each person going.
Plus the GAR as usual.
It’s not too bad.
The website for the public health form is crap but all UK Govt IT is utter crap, specified by monkeys and written by monkeys employed by big IT firms who make their money fulfilling contracts for stuff they know won’t work and then billing heavily for making them “sort of” work. They cannot even organise things so that everybody ever signed up doesn’t get a BCC with everybody else’s contacts (happened with the govt GAR form gateway; I was tempted to invite them all to EuroGA)
There are some areas where you have to put in garbage to be able to continue.
