All replies to your message are from overseas members. As someone UK based I would suggest if you wish to fly in Devon at 4am - go for it! Who is going to stop you at that hour?
Understand that, but the OP asked . . .
is just one of those stupid rules that allows zero flexibility for the benefit of no one.
Rules from CAA and other authority (land use) are generally 24/7 I imagine, common sense / flexibility does not usually apply.
It'd be nice if common sense could be applied, but that would no doubt lead to many differing viewpoints and possible conflicts.
Motorways at 4am might be light / nil traffic, doesn't mean it's ok to do the ton, and most wouldn't.
It often boils down to the individuals risk adversity to authority.
My council bans model aircraft from their parks, it's a huge council area.
The rule is not enforced, no signage in any park, it's buried in their bylaws and takes a lot of specific searching to find it.
There are parks so isolated, mid week, work hours, it's very safe to go in there and do a couple of quick test flights for 1/2 hour, without anyone coming by or risk.
????
Now if someone with their particular common sense thought it does no harm to go and fly there on a Saturday / Sunday morning, just follow the drone code / rules. often dogs owners, people exercising, taking a walk and passing through, complaints made, councils policy might be brought to bear a little more stringently . . . signage put in, rangers patrolling / enforcing, warnings / fines issued.
Slippery slope.
I'd certainly fly in the OPs case, as long as airway clear to go, TOAL well away from any homes / parks, landing pad on the beach firm sand, out of earshot of anyone else on the beach (other photographers etc).
OP is wise to take things slowly, only a new pilot with a very pricey drone, probably just looking to take it up, get some nice elevated photos / video, keep it pretty quick and safe.
Happy and safe flights.