When the cash and other available assets of an insurer with guaranty capital shares are exhausted, such part of the guaranty capital fund as may be required shall, with the approval of the superintendent, be drawn and used to pay losses then due. When such fund is so drawn upon, the directors of the insurer shall make good the amount so drawn by assessments upon the contingent funds or notes of the insurer or by borrowed funds as provided for under section 3415; and unless such fund is restored within 6 months from the date of withdrawal, the holders of guaranty fund shares shall be assessed in proportion to the amount of such shares owned by them for the purpose of restoring such capital. [PL 1973, c. 585, §12 (AMD).]