Have you thought about provisional insurance?

Sometimes it is cheaper to find an insurer who is cheaper for Full insurance, yet more for provisional, and so to save money you can take out a policy for provisional only.
Try collingwood for example; I have a testimonial from a friend who recommends them:
http://www.collingwoodlearners.co.uk/
However, it is of course usually cheaper to stick with your full insurer.

As with all insurance tips: TRY EVERYTHING, FIND OUT EVERYTHING, SAVE EVERYTHING!!