Chris we had driven about 40,000 miles in our XC60, we had no adaptations. I called them and they offered a 1 or 2 year extension. I took 2 years as its a no brainer.
We extended as we loved the car, nothing to do with finacial considerations.
If you can get the car you want on the scheme then extending, obviously, has no advantages, but at this time there are few cars on the scheme so if there is nothing that is suitable for you, and you like your current car, then extend and take the 2 year option if available.
The only person who got all his work done by Friday was Robinson Crusoe.
Anything i post over three lines long please assume it is an article lol.