all down to YOUR ( or your mums ) declaration
For example
is it your car
-
who is the registered owner
who will be the main driver
?
if you say your mum to these when it is infact your car, and you will be the main driver, then you are breaking the law.
Very difficult for the insurance companies to prove, but if they smell a rat, they will do anything to get out of paying if you are unfortunate enough to have to claim
try getting a quote with you mum as a named driver, I am am both my daughters policies now as it reduces them down by a LARGE amount.