(a) The council by rule may adopt a system under which licenses expire on various dates during the year.
(b) For the year in which the license expiration date is changed, license fees shall be prorated on a monthly basis so that each person pays only that portion of the license fee allocable to the number of months during which the license is valid.
(c) On renewal of a license on the new expiration date, the total license renewal fee is payable.