DS used to be great at agreeing a time to be home after a night out, and I'd generally wait up to see he was home safely.
Recently he's become quite vague about times ("won't be too late, just going for a pizza!") then texts at various points to update ("all going back to X's, might be a bit later!") again ("I'll be back after I've been to Y's to watch a film, shouldn't be much after 1am") and again ("actually stopped off at Z's, all ok!")
Full marks for keeping in touch but I'm exhausted from waiting up or else going to bed and being woken by all these texts! But I can't work out whether the solution is to say "be back by midnight" or whatever as we did when he was a bit younger, or else to give up on curfews and waiting up all together and just expect him to let us know if he's sleeping over somewhere else. The latter feels like a bit of a leap and I'm not sure what the normal age would be for that and whether I'm being a bit slack or else far too cautious. I deliberately haven't given DS's age here as I'm interested in the age other people think this would be a reasonable thing to do.
If it makes any difference, we live in London and DS gets around on public transport until about 11 and then Uber, which he pays for himself.