My partner and I are going to London the last week of April, and then going around Ireland for the first two weeks of May. We're taking my mom and youngest sister, and my mother-in-law. I have to say I'm still definitely feeling the pressure. I'm immunocompromised but got lucky and had a relatively mild case of COVID (I mean, it sucked, but considering I had spent two years expecting to be at least hospitalized for it, it was way better than I had even hoped for - I happened to get it within the whole "2 weeks after the booster for immunity" period which must have helped), as did my partner - but any natural immunity will be waning by the time we're there and there's no chance of a 4th shot. My mom and sister also got sick, and should still be relatively safe while we're there - but now even that is worrying me since they're likely to feel less personally paranoid than the rest of us! My mother in law has a 22 hour trip to get there, spending time in 3 different airports, and that's a very big concern - though I think she's optimistically trying to think of it as an opportunity to never have to remove her mask while actually on a plane, since she can mostly wait until she can hide away in an airport to eat.
So far everyone still wants to go, but I still worry that's more out of feeling restless and like it's now or never, rather than a real consideration of the situation. Because our trip in Ireland would be relatively COVID-friendly (easy to just be in the rental car or exploring mostly outdoor sites if we need to), we're still monitoring what might need to change for the London portion. Beyond masking, of course, we intend to get take out as much as possible (being close to Borough Market should help!), walk and bus as much as possible, and are focusing more on walking tours and the like instead of indoor sight-seeing. We also haven't booked any theatre tickets yet, even though in previous years that would have been the main reason to go to London, and are waiting to see about cases/how many tickets to each show have been sold. And worst comes to worst, our flights from London to Dublin are changeable, and we could skip over London except for a lay-over.