(1) Any employer may at any time terminate his or her status as a self-insurer by giving the director written notice stating when, not less than thirty days thereafter, such termination shall be effective, provided such termination shall not be effective until the employer either shall have ceased to be an employer or shall have filed with the director for state industrial insurance coverage under this title.

(2) An employer who ceases to be a self-insurer, and who so files with the director, must maintain money, securities, or surety bonds deemed sufficient in the director's discretion to cover the entire liability of such employer for injuries or occupational diseases to his or her employees which occurred during the period of self-insurance: PROVIDED, That the director may agree for the medical aid and accident funds to assume the obligation of such claims, in whole or in part, and shall adjust the employer's premium rate to provide for the payment of such obligations on behalf of the employer.