The commission by rule may adopt a system under which license and registration fees required by Section 116.032 of this code expire on various dates during the year. For the year in which the license and registration expiration dates are changed, license and registration fees payable on a specified date shall be prorated on a monthly basis so that each licensee shall pay only that portion of the license and registration fees that is allowable to the number of months during which the license and registration is valid. On renewal of the license and registration on the new expiration date, the total license and registration fees are payable.