Ex son in law

I feel your ex-SiL is being very rigid and seems to be being deliberately difficult and unfair to the children. He could have objected much earlier so that your daughter had time to change the arrangements.

Unfortunately, some exes are like that. I have no answer to the current problem but I would suggest that, if the court order is as he says, your D sticks absolutely to the rules in future and watches closely what her ex does. If he transgresses even slightly she should object - the court order applies to both of them, after all.

Will they actually miss their afternoon mark? So it wouldn’t affect their attendance figures.

Your D will have her copy of the court order so she should be able to check the content herself.

I may be wrong but presumably he has given his consent for the children to be taken out of the country for this holiday, so I can't see having done so he'd have a leg to stand on objecting them to missing 2 hours of school in order to go on the holiday he as already agreed too.

This is not advice but if it were me, I'd collect them at lunch time in case he turns up at the school in the afternoon to cause a scene and prevent them being collected early.

Probably entirely the wrong thing to do but that's me.

Hopefully Germanshepherdsmum will be along to give you the benefit of her legal mind.

What a complete nightmare! Suggest she contacts her solicitor pdq and also checks the court order.

Let your dd manage this

If I were her, I would have known this may happen and be ready for this

I would be ready to change the flights

Unless I read your post improperly, your daughter is playing loose with the Court Order. If true, perhaps she needs to change the children's flights.

You state he’s ‘saying’ the Court Order says this, does it? If so, a quick solicitors call should clarify, suppose they had a hospital appointment at short notice, common sense would prevail.
I wouldn’t have told him.

That's a pity. It seems that your DD is planning on violating a Court Order which could backfire on her upon return and jeopardize her custody of the children. I think I would change my travel plans, regardless of the cost, and have an agreement in writing before taking them on holiday. It seems like a planned, legal ambush on the ex's part.

I don’t imagine the school will stop here but it could look poorly for your daughter if sends the evidence of such (school attendance record and proof f contact saying he didn’t agree to it ) to his solicitor and it is shown as part of a pattern to the courts