He can't just pick and choose

[ChickenTikkaTellMeWhatsWrong]

Me and my ex share 2 DC, he's been away in the Isle of Man working since November, coming to see the boys for a day or 2 every so often.
If you have read any of my previous posts, he previously had a girlfriend who he was going to go on holiday with, but anyway they broke up about 6 months ago.
He told me about a week ago he's got a new girlfriend who he's been seeing for about 3 weeks now and he permanently came home from his job on Tuesday where he spent the day with the boys.

I then messaged him yesterday to ask if he could collect them from school as I'm in uni. He said no as he's gone to his girlfriend's (who lives about half an hour 45 minutes away from me, so he says). But he will see them on Sunday. He's also moving in with her in a few weeks, and doesn't have a car.

Am I right in thinking that he's just been away for months, comes back and sees them 1 day and then bogs off till Sunday. He can't see what he's done wrong.
I've told him he needs to get his priorities in order, as if it was the other way round, say he had the kids for the night and then asked what time I was picking them up, but then said I'm not but I'll see them sunday. I know he wouldn't be happy.

He can't just pick and choose when he wants to be a parent, it's absolutely frustrating.

I've told him we need to get an arrangement in place, as I'm not happy to wait for him to tell him a few days before what days he's having the kids.

I just wanted to vent, but don't know whether I'm right in what I'm saying.

Thanks for reading 😊

Of course you're right. You're both parents...you share the responsibility

Tabby I'm surprised that your kids tolerate this as and when routine,

If I were you, I'd decide when you want him to have access to your dc, eow, one night in the week etc. Tell him this is when he can
see them, if he doesn't turn up then that's his loss.

You're right, he can't just pick and choose, but you also need to set out your stall. You can't really ask him to collect the dc with a few hours notice and expect him to be there every time. I share dc with my ex and tbh when I don't have the dc I tend to be away or off doing something so if he dropped a 'can you collect the dc from school' chances are I'd struggle to get there in time.

Thanks everyone for your advice, I have told him we need to get a proper routine in place asap.
@sunshineANDsweetpeas yeah I cam see I was being unreasonable about expecting him to do that with that much notice, it's not really that, that bugs me it's the disregard that he will just see the boys this day or that day.
I didn't moan to him when he worked away as that was his job and he needed money, but now he's back he should be where I'm coming from in regards to co-parenting. Hopefully he will get it soon.