To think there’s nothing I can do?

So if you do 50/50 is the expectation that there is one set of everything at each house… like school uniform etc or will he expect you to send everything for his week ?

Yes - but also remember he has equal PR and as the OP also doesn’t have a court order she has no more right to any custody than he does.

a court order so always worth it

One with very low self-esteem and poor boundaries.

I would have done handover in a Monday, so one drops off at school and the other picks up.

My goodness I would have hated this arrangement as a child. It’s not fair on them to be left with a stranger

Take him to court is how you challenge it. This is in his best interests not the children’s. The courts don't care about his interests only the children’s

Send him an extremely detailed proposed schedule.. Include after school clubs /dentist /Dr /hairdresser /parties /library trips /play dates /detail clothes /shoes sizes as he would be expected to provide these things in his time . Tech also.. As the dc won't be carrying them back /forwards at risk of damage. Suggest he logs the agreement with his solicitor so yours can agree and have iy drawn up as a proper agreement..
Watch him backtrack.

At least with the ages of your children they will be able to express their wishes and feelings bro the Court via CAFCASS.

What kind of a woman will agree to this? Is she an aupair he got himself involved with?

It sounds like you quite want this to happen though Op.

I would challenge this in court. No way is it in the children’s best interests to spend half their time being looked after being their dad’s new gf or in the home of a parent who isn’t there.

Theyre better off being with a parent who is about, and their dad paying maintenance to make sure you can give them a good standard of living.

This is a dreadful situation for your children. I think you have to take him to court to challenge the 50/50. I'm hardly a helicopter parent but a girlfriend of three months, you know nothing about her and she is a stranger to your children. And he's only doing it to avoid paying. Another shit dad.

This sounds a very mature course of action. The children are old enough to let their dad and you know if they’re not happy. I’d also let school know the arrangements and they can check in with the children to make sure they’re ok on the weeks they’re not with you.

Ex-dp has decided he wants 50/50 custody, so he doesn’t have to pay child support.

Why does he get to decide?
The childcare he’s providing (by way of GF) doesn’t seem to be in your children’s best interests OP.

Can’t you decide, no, this is not okay?

However, it’s not clear exactly how much childcare GF will be providing as you just say it’s around his shift work. Unless it was for very short time periods I wouldn’t be ok with this.

Is she putting them to bed at his place and staying there with them until he gets home? Or are they actually staying at her place overnight when he's working shifts? If it's the latter, those nights typically would not be counted as part of his total for child maintenance payment calculations (at least in England).

I would first go and get legal advice. I imagine the lawyers first step would be to write to your ex objecting to his proposal on the grounds it is not in the best interests of the children to be cared for by an unknown adult. You would discuss with solicitor what you want to say as a counter proposal, ie he has them when off work and that childcare be with familiar adults.

Advice from solicitor about what would be likely if you took this to court to try and prevent it happening. I’d be guided overall by their advice, but if I could fight it I would, I’d be so upset about this.

Are you on speaking terms with your ex? Can you ask him to consider how he’d feel if you had a partner of 3 months caring for your kids?

You respond to him by email;

”I have considered your new suggestions for having the children and I don’t feel it’s in their best interests. I’m happy to continue with the current arrangements, or move onto mediation/court order if you’d like to formally press ahead with your proposal.

Kind regards,
Naan”

You go to school and pick then up as usual. Do you think the school will send them home with some unknown woman over you?

What is in the court agreement? If it is not currently 50/50 then he hasnt a leg to stand on.

The only thing you can do is go to Court and get a formal Order. It’s a difficult situation but unless you feel the children are not happy or in danger you may just have to go with it.

A GF of 3 months doing school runs and childcare sounds like a really bad idea. Too early to introduce them. Too much expectation on a new partner which could lead to her resenting the DC and not being very nice with them or could lead to them breaking up. There's a good chance they will break up anyway, it's very early, they will still be in the stage of figuring each other out.
I'd refuse 50/50 and let him take it to court. See what happens there. They might separate before it gets in to court, he probably won't be so keen on 50/50 without a woman he can pass the care on to.

Can’t see this lasting longer than a week till she’s pissed off. He doesn’t even know her properly at 3 months what if she’s a pedophile or something?!