California Code, Business and Professions Code - BPC § 2892

Licenses issued under this chapter prior to January 1, 1974, shall, unless renewed, expire on the last day of the month following the month in 1974 in which the licensee's birthday occurs and at two-year intervals thereafter on the last day of the month following the month in which the licensee's birthday occurs.  Licenses issued under this chapter on or after January 1, 1974, shall, unless renewed, expire at two-year intervals on the last day of the month following the month in which the licensee's birthday occurs, beginning with the second birthday following the date on which the license was issued.  To renew an unexpired license, the licensee shall, on or before each of the dates on which it would otherwise expire, apply for renewal on a form prescribed by the board and pay the renewal fee prescribed by this chapter.

The board shall give written notice to a licensee 30 days in advance of the renewal date and, 90 days in advance of the expiration of the fourth year that a renewal fee has not been paid, shall give written notice to the licensee informing the licensee in general terms of the provisions of Section 2892.4.