This was tough for me because he was often with his dad of a weekend and dad would go out and leave him to his own devices.
So once I was ready to be less strict he'd inform me, "but mum, I already come in at stupid o'clock when I'm with dad".
(I checked, he was telling the truth) so I didn't want his independence to regress and he is being sensible.
So now I play it by ear, I'd rather know exactly where he is and give him a time to be home by, but if he can't get here, (missed busses etc) there's no punishment as long as he messages me or calls.
He also knows I'll always pick him up or send a taxi if he's stuck.
I think it depends on what your son is doing, mine is nothing like i was at his age, he's sensible for a start, I behaved like the love child of Courtney Love and Charles Bronson, so I know if he's ever seen trouble etc he's the kid who makes sure he and his pals leave, if need be ring the police etc.
Me at 15 would be right in the middle like a small hooligan, so I can't and don't judge him by my standards.
His friends are also lovely kids, so that gives me confidence, because they're not causing any drama etc, just playing football or sat in each others houses.
If I suspected he was fighting, vaping, doing drugs or being a dick to locals, he'd be on house arrest, but as it stands, in a couple of years he's free to leave home, next year, he can drive etc so I hope giving him the independence and trust will pay off, even if I'm a nervous wreck.
And credit where its due, he will usually just send me a thumbs up or something mid way through his night.
It's so bloody tough this age, especially when it's absolutely rife with knife crime and really extreme violence for teens atm. But as scary as it is, we can't stop our kids from growing up because of the actions of others, same way we can't let terrorism stop us enjoying arena venues or the fear of a car crash driving, it's terribly scary, but life has to go on.