Good to hear Albacore. We are just back too. Towed up the A9 to John o Groats, back down through the Highlands to Lairg, then across to Clachtoll, down to Ullapool then back down A9 to Dundee.
We stopped at some CC sites and some some commercial. I never asked on CC sites due to previous reply, but the commercial sites were happy enough for us to charge.
It was a bit of a relief running on electric after the noisy engine whilst towing. As you can imagine there were a few big hills so the ICE was working hard. Had a few " reduced propulsion" messages, but all worked well.
Had to stop for petrol more often due to small tank and the towbar seems quite low, so van was quite nose down. The rear end was quite low too as the boot was packed. But well get things moved about with more trips away.
Good luck in France!