Car Insurance for 18yo going off to Uni

My 18yo son currently has his own (very cheap) car and first year (very expensive) car insurance which is due to end at the end of August. He hopes to go to Uni in Scotland in September and he won't be taking a car with him.

He will definitely want to drive when he comes home for hols etc as we live miles from anywhere, so my question is would it be better to keep his own insurance going? If he doesn't insure a car for 2/3 years under his own name will it make a difference in the long term?