Slowly but surely, some information is being released.
So, in short: for private flights, until June 2022, all airfields in UK can still be flown to and from (directly) when coming from or going to say FR, NL, BE, GER, etc. This is good news. No restriction of only using customs-designated aerodromes.
After that however, airfields will have to have a „certificate of agreement“ in order to be able to receive such flights.
Since many (small) airfields have such CoA even today (for enabling direct flights to and from the CI, for example), I can only immagine that obtaining such CoA is not too onerous. Could someone here tell what exactly must be done/agreed/guaranteed in order to obtain such CoA?
The big unknown is still notice periods for the GAR for such flights after 1/1/21. Will it remain 4h? Or will it become 24h? That will make all the difference on whether flying to the UK will remain „practical“ or not.
What is the downside of filing a GAR 24+h in advance and then not going? The GAR is just an email, right?
Sure, that‘s theoretically possible. But GA does not really work like this. It works by short notice decisions. Especially when the UK is involved, the short term weather forecast or report often play role.
4 hours is a non-issue. You decide to do the flight and then plan the rest, head out to the airport, prepare the aircraft and fly. So, unless you depart from 2LK, by the time you land, 4 hours will be over.
In case of 24h, a UK pilot wouldn‘t even be able to make the decision for a daytrip to France on the evening before, as that would be less than 24h, for departure, but likely even for coming back.
But as I said, the notice periods required will still have to be seen. I am rather confindent that it will not be 24h.