Right Mick. Sounds like you need to speak to someone at the Broker's who knows about this option when insuring a kit then.
I made it quite clear that I wasn't going to use the car immediately but was not offered this option.
If taking that option keeps you off the DVLA ( or is it VOSA?) database of "on the road" cars, and away from a requirement to tax the vehicle, then it's important to be told about it!