Hi @HamishC - I was in a similar situation myself about 18 months ago when I moved to the EU (Sweden in my case rather than France), and a number of the queries you have were shared by me when I moved. I’ll add my experience here and hopefully some of it will be useful!
Prior to my move I had a similar quantity of wine to consider. The stuff that was in my physical possession or duty paid in TWS was relatively straightforward in the end. I found it difficult to find info to help but the destination country’s customs agency will have the forms you need - it’s probably just a question of asking Google the right question worded in the right way! Once you have a shipping company lined up they will also have dealt with this sort of thing countless times and be able to help.
In the case of Sweden, and I imagine the rules across Europe will be similar, all of the wine could be shipped with the rest of my possessions but needs to be accompanied by a form detailing what was in the consignment - and I was also advised to provide as many purchase records as possible with evidence that the wine was duty paid etc. This form then accompanied the removal company in case they were stopped at customs. In my case nobody checked, but all paperwork was in order just in case. I did not physically accompany my wine (nervous times!) and nor were there taxes due as all of the wine was duty and VAT paid in the EU.
The rest of my wine was either bonded (very small quantity) or still awaiting delivery from earlier EP campaigns. For those bottles I effectively waited for them to arrive or slowly mature and my plan is to periodically collect them myself from the UK, as I plan to drive to the UK once in a while for holidays etc. In those instances I will either arrange for wines to be duty paid and delivered to somewhere convenient or arrange collection myself as I pass by Stevenage. COVID allowing I will probably make one of those trips prior to the end of this year and the forthcoming B-word shambles. That is a journey which is easier from Paris than it is Sweden
After the end of the year I will still have wines arriving in TWS from EP offers, or occasional cases that catch my eye and warrant a period of rest in reserves. If wine allowances become super restricted (which I don’t think is in anyone’s interest) then I will look into arranging for TWS to ship those but that is not very economical and will probably lead me to buying less from TWS. I hope common sense prevails and I’ll continue to be able to move reasonable quantities around for personal consumption.
I have never considered moving in-bond wines from one country to another and retaining them in-bond. Given differing local duty rates I think that might be tricky, but as I said it’s not something I considered doing.
Hope that helps! Happy to chat about the joys of living and working in the EU
Good luck with your move!