(a) In the event of the cancellation of a policy of automobile insurance, as defined in Section 143.13, by either the company or the policyholder, the company shall refund the unearned premium pro rated to the date of cancellation. In no event may the refund of unearned premium be computed by use of a short rate table. Refund of the premium shall be without prejudice to any claim arising prior to the cancellation.
     (b) The refund shall be made by the company within 30 days from the following:
        (1) the date of the notice of cancellation by the