California Code, Financial Code - FIN § 18609

All statutory, regulatory and contractual restrictions providing that the insured or the insurer shall not cancel the insurance contract unless the insured or the insurer first satisfies such restrictions by giving a prescribed notice of cancellation to a governmental agency, the insurer, the insured, the holder of a security interest in the subject of the insurance, or other prescribed party, shall not be affected by the provisions of this division. However, any cancellation notice period required by such statutory, regulatory or contractual restriction shall not be cumulative to the period required by Section 18606 or 18608. If cancellation of the insurance contract is initiated by the company under the terms of this division, the insurer shall (in accordance with the requirement for a prescribed notice), on behalf of itself or the insured, give such notice to the governmental agency, the holder of a security interest in the subject of the insurance or other prescribed party; and the insurer shall determine and calculate the effective date of cancellation (in accordance with the terms of that prescribed notice) from the date it receives the notice of request for cancellation from the company. In no instance shall the effective date of cancellation be prior to that established by the company.