That doesn’t seem right, I wonder what the ABI would say about it!
Have you tried getting a quote from RSA, Direct Line, Esure or even an insurance broker and maybe pay a premium for the first year just to get your NCD, you can move over the following year.
When I had a Company car I had no issues getting claim free years turned in to NCD’s and taking them with me on renewal the following year, albeit that was a few years ago now. I’ll check my emails, but I’m sure it was either Direct Line or Esure I went with.