13 Jan 2022, 10:41

Hi @paul-phillips-2 Welcome to the forum. You haven't mentioned what satnav device you will be using, I ask this because you have planned your route on the (Default) OpenStreetMap. If you are using MRA Navigation or a Garmin device, it would be better to use the Here map or plan your route on the TomTom map if using a TomTom.
I would also suggest taking a ferry to Spain to start your tour, yes it's more expensive but when you cost in the price of the channel crossing, fuel, wear and tear and probably one night in a hotel, there's not much in it, plus your holiday starts as soon as the ferry docks. The ferry leaves Plymouth about 5pm and arrives in Santander about 2pm the next day.
Where do you propose stopping each night? What are the route point numbers on your route for your overnight stops? Accomodation tends to be cheaper on the Spanish side.