California Code, Business and Professions Code - BPC § 2538.53

(a) A license issued under this article expires at midnight on its assigned renewal date.

(b) To renew an unexpired license, the licensee shall, on or before the date of expiration of the license, apply for renewal on a form provided by the board, accompanied by the prescribed renewal fee.

(c) Temporary license holders shall renew their licenses in accordance with Section 2538.27, and apply for that renewal on a form provided by the board, accompanied by the prescribed renewal fee for temporary licenses.

(d) Each duplicate license issued for a branch office shall expire on the same date as the permanent license of the hearing aid dispenser to whom the duplicate license was issued.  These duplicate licenses shall be renewed according to subdivision (b).