I do believe I spoke to you about this one via PM but never actually made a post in here for anyone to see who'll end up in a similar situation.
If any of you ever did find yourselves where you have 2 cars and are looking to swap them over but only need to use one on the road, the first thing you need to do is ask the question, "if I leave it on my drive, will someone pinch it?". If the answer is no, simply SORN the car you aren't using and insure the one you are using, eg. Bought a new LR and want to do it up whilst you are still using the day to day work horse, SORN the LR and continue using the daily driver on its current policy.
In the case of wanting to use our new purchased LR, call your current insurer, swap the LR with the daily driver, call the DVLA and SORN the old car.
But, if the answer is "yes, my car will get nicked" it's almost the same as above, but apart from SORN'ing it, all you need to do, is take out something called "laid up" insurance ie. an accidental damage, fire and theft/ just fire and theft policy, that will cover your car for 0 miles... In short, to sit there and do nothing. This kind of insurance can be difficult to find for cars parked on the drive/not in a garage, but some companies will be able to.
I hope this made sense, and hopefully will help a few people in the future.
Have a nice evening,
Ed