Hi Everyone, I am pleased to say that FINALLY I've got the correct tyre sizes on my log book. It took a two hour wait and a (roughly) 2 pound fee today. The whole episode has cost me around 260 pounds, and loads of my time, but I can use the new 215/40's on the rear at some time in the future.
HOWEVER:
Ultimately I have to blame myself. When I bought the car 4 years ago in Germany, the seller gave me the correct documents from TUV and I took these to the local office here along with various other documents. They issued me with the log book, but I didn't really look (or think about) the tyre sizes, I saw that both 15 and 16 inch wheels were listed but I didn't think about the detail. My previous TF had 15 inch wheels and had always passed on the tyres.
I got away with it 2 years ago, but not this time, lesson learnt.
Moral of the story - very carefully check your new log book, especially if you are importing the car from another country.
Thanks to all of you who showed interest in this.
Keith