For now, I'm trusting the comments from the various trade and campaign groups on that point. They've been in meetings I haven't with organisations like HMRC, and they all seem to be telling a similar story, though also with a similar lack of detail so far.

I completely agree that some official guidance we can all see and act on is well overdue on this point. There are several issues connected to the new EU VAT rules that are being widely reported but I'm having trouble finding official citations; probably the most important one I've come across is the legality or otherwise of declining to sell to customers in the EU but outside your home nation in an attempt to avoid the whole mess.