Cal. Unemp. Ins. Code § 1243

A decision of the appeals board on an appeal from a denial of a protest under Section 1034 or on an appeal from a denial or granting of an application for transfer of reserve account under Article 5 (commencing with Section 1051) shall be subject to judicial review if an appropriate proceeding is filed by the employer within 90 days of the service of notice of the decision. The director may, in writing, extend for a period of not exceeding two years the time within which such proceeding may be instituted if written request for such extension is filed with the director within the 90-day period.