Cal. Insurance Code § 1063.18

(a) Nothing in this article requires a final determination of a claim in an insolvent insurer’s liquidation proceeding before a covered claim may be submitted to the California Insurance Guarantee Association (CIGA). Nothing in this article requires a claim to first be determined and approved by the liquidator before CIGA pays and discharges a covered claim. If a claim is presented to the association and all requirements under paragraph (1) of subdivision (c) of Section 1063.1 for processing a covered claim are satisfied, the association shall proceed to process the claim for payment under this article. (b) If the association provides a written denial of a nonworkers’ compensation claim, the person asserting the claim against the association shall have one year to bring an action challenging the denial, including an action for declaratory relief. If the written denial is based on a failure to exhaust other insurance available to pay the claim, a claim shall be reasserted against the association within six months after all other insurance has been exhausted.