OK, so just got back from L2K to be met by Herr Flic and partner in lovely tight black uniforms. Quite cross, because amongst all the forms I'd filled in I hadn't done one of these:https://visas-immigration.service.gov.u ... cator-form
This form lets them a) monitor your performance of 14 day self-isolation, and b) inform you if any of your fellow travellers come down with the 'rona.
In a typical bit of Britishness, it was worth sending out a brace of officials (on a Sunday) to someone who had a) come from a country exempt from self isolation requirements and b) in a plane containing only his household. Both facts apparent from the (properly completed) ordinary GAR. Anyway, we were forced to spend half an hour sitting on the wing trying to work through the inept online process before we were allowed to rush off to the toilet.
But we're British, damnit. And an uncompleted form is treason against society. So don't forget it!