(1) A life insurer may, under such policy provisions or agreements as have been approved by the commissioner consistent with this section, contract for and accept premium deposits in addition to the regular premiums specified in the policy, for the purpose of paying future premiums, or to facilitate conversion of the policy, or to increase the benefits thereof.

(2) The unused accumulation from such deposits shall be held and accounted for as a premium deposit fund, and the policy or agreement shall provide for the manner of application of the premium deposit fund to the payment of premiums otherwise in default and for the disposition of the fund if it is not sufficient to pay the next premium.

(3) Such fund shall:

(a) Be available upon surrender of the policy, in addition to the cash surrender value; and

(b) be payable upon the insured's death or upon maturity of the policy; and

(c) be paid to the insured whenever the cash surrender value together with the premium deposit fund equals or exceeds the amount of insurance provided by the policy, unless the amount of the deposit does not exceed that which may be required to facilitate conversion of the policy to another plan in accordance with its terms.

(4) No part of the premium deposit fund shall be paid to the insured during the continuance of the policy except at such times and in such amounts as is specified in the policy or in the deposit agreement.