I've got some sympathy for those that traveled, people do want to get away after the last year and I understand that. But the virus is still around, still changing, the Government's travel advice policy is a mess, so there are known risks to travelling overseas right now, and it's not like this change in country advice has never happened before.
When you travel in these times, if you have any sense, you simply have to be spending a few minutes on a basic assessment of worst case scenario... "What if it changes and I have to come back? Could I even get back earlier? Or could I afford the time at home to do the quarantine? Or maybe I can afford the costs of the 5 day test to release?" Weigh those up, and if the answer is that you can't afford to quarantine, change plans etc, then you really shouldn't be going beyond Brighton. If you can live with the risks then go, but these are things you should be considering before you take the risk.
For those who weighed up all the potential problems and decided they could absorb the challenges, I've got respect, you tried, it went a bit awry, but you thought about it and you've got a plan B. To the other ones moaning about the queues at the airport, or the lack of customer support that comes with that 40 quid Ryanair ticket, I've got less sympathy for... not none, but certainly less.
Oh, and travel insurance. Buy it, and make sure it covers costs brought on due to Covid travel advice, it costs next to nothing compared to the holiday.