Cal. Rev. & Tax. Code § 677

The board may issue a temporary certificate to an assessor who is newly elected or appointed or to any person newly employed by the office of the county assessor in order to afford the person the opportunity to apply for and take an examination, the successful passage of which would qualify the person for a certificate pursuant to this article. The board shall not issue a temporary certificate for a duration that exceeds one year, unless the person has been duly elected or appointed to the office of assessor. The board shall not renew a temporary certificate.