Dirty stop out cat...can I give a cat a curfew?

[Deargodletitgo]

I have two cats, one wears a tracker and pops in and out, until he's locked in around 10ish at night. My girl tends to go out for longer periods, all-day if it's fine and after dinner on a good evening she's back at 8 or 10 or 12 or 2 am....

8 and 10 I'm fine with. Given I want to have them both tucked up inside before I go to bed, 12 and 2 am are less acceptable.

Locking her in at dinner time leads to much abuse and whinging.

I think I may know the answer to this, but is there anyway I could encourage her back at a reasonable time (calling her name doesn't work and as she doesn't wear a tracker not sure where she is). I could get her a tracker but she's got a tiny neck and head and doesn't wear a collar.

Alternatively, should I give up on the locking in at night?

Mine is very much a nocturnal cat but it does make me worry. I’ve tried constantly to feed him at night, lock the cat flap and also placed heavy things in front of it including bins, piles of text books and buckets of water. He won’t be dissuaded though and just barges them out of the way and bashes the cat flap until he is out. I’ve now given up and got tracker for his quick release collar instead. It turns out he can do 4 - 5 km abnight just catting about and being nosy. Luckily I’m in a fairly rural area away from main roads but I still worry about the little furry bugger. I adopted him 7 years ago from Blue cross when he was 18 months and he was advertised as an indoor cat. He very much isn’t but is the biggest love bug in the world so I forgive him and his nightly adventures.