-Ralph-

Read the terms and conditions of the policy.

Immediately in the majority of cases though, insurance companies don't write many T&C's that work out in your favour.

Elephant charged me when I told them about 6 month old points on renewal, saying that I should have told them straight away, so they would be billing me for the 6 months cover I had had that would have been at a higher rate had I told them. I didn't renew with them and told them they could take me to court if they wanted the money, and after a couple of demand letters it went away, but nonetheless they could have pursued it if they wanted. If they hadn't already sent me proof of no claims with the renewal quote, I'd have had no choice but to pay it.