A few points in response to comments.
Whether the PM is still unfit from his bout of Covid is irrelevant, the biggest failures took place throughout February and into March well before he had it. Everything else leads back to that. Also although implications of having the virus aren’t fully understood I don’t believe they include allowing lockdown-breaking drives to County Durham to go unpunished.
Acting decisively in this case is to be applauded and I personally agree with it. But yet again it’s been done in an inconsistent and slapdash way. It should have been immediate or from 3am for example, after all flights are in. As it was, you had flights arriving just before midnight from higher risk areas with no quarantine and some a few minutes later who are locked up for 14 days.