Moving Wine Cellar

Customs duty and general hassle commonly means it's an expensive headache to move stuff.
I can't help you with the problems as such, just suggest you have a serious party if moving it proves too difficult.
To define 'party' - a gathering the town will talk about for the next ten years.

Yeah,that’s kinda what I was thinking.

I have looked into this. Without penalty or tax you can bring wine for 'a normal home wine rack'.
My 400+ bottle rack is not considered 'normal'.  I will drink a lot of wine before moving and move only the ones which are old and precious - about 40 bottles. Not  a great loss, as wine is cheap in Portugal and I can rebuild without too much expense. I will miss my collection of 2015 Rhone and Tuscan wines.

That's what I'm hearing.  I just put a moratorium on buying reds and will drink my cellar down as far as possible in the next few years.  By the time I'm ready to move, hopefully the number of bottles will be reasonable and I can pick the best to import.