How do I change iTunes country with family sharing and child accounts?

I've moved from the US to the UK and I'm trying to change my country in the App store on my iPad. I have family sharing setup, and a child account included in the family sharing.

The problem is that changing countries demands that I disable family sharing first. But when I try to do this, I can't, because I have a child under 13 on my family sharing account which cannot be removed from the family. The child account can be transferred to another family - but I don't have another family!

So it looks like I have to delete my childs account, then disable family sharing, then recreate it all in the UK. Hence losing anything bought by my child and causing a lot of disruption.

Is that really the only way to do it or is there any better method out there?