Last Mets out of Town are just before midnight on most lines (about 23.15 to Mcr Airport) on a Saturday night. Used to be later than that about ten years ago, you could still catch them at around 00.35.
Buses are fairly similar these days.
Until about ten years ago buses used to run through the night. Was it the X71 Magic Bus that used to run from Town to Moss Side, Chorlton, Stretford, Sale and Alty? And it was only about a quid on that bus! I used to get that at about 02.30 every Saturday night/Sunday morning for years, they were always busy n’all so it’s not like they were a dead service (as my Sister used to moan about me passing out at the back of the top deck and she had to look after me and make sure I wasn’t robbed by all the undesirables and piss heads getting on at that time… although when I went out without her I’d still pass out up there when I was on me Todd and I was never robbed!).
The train still runs until about 00.35 from Piccadilly to Mcr Airport on a Saturday night.