(a) The corporation may, at any time and from time to time, issue refunding securities for the purpose of refunding any securities of the corporation theretofore issued under Section 22-21-182 and then outstanding, whether or not such securities shall have matured or are redeemable at the option of the corporation at the time of such refunding; provided, however, that the maximum principal of securities that the corporation may at any time issue for refunding purposes shall not exceed the sum of:

(1) The outstanding principal or face amount of the securities being refunded;

(2) The unpaid interest accrued thereon to the date that such refunding securities are issued;

(3) Any redemption premium necessary to be paid in order to redeem the securities to be refunded; and

(4) The expenses estimated to be incurred in connection with such refunding.

(b) The principal proceeds derived by the corporation from the sale of any refunding securities shall be used only for the payment of the principal of and the interest (and premium) on the securities being refunded and for payment of the expenses stated in subdivision (a)(4) of this section; provided, that such proceeds may, if in the judgment of the board of directors of the corporation such is necessary or desirable to effect an advantageous refunding, use a portion of said proceeds for payment of principal of and interest on such refunding securities themselves and the remainder of said proceeds for payment of the securities being refunded and of said expenses; and provided further, that in any event any portion of said proceeds that shall at the time not be needed for any of such purposes may, pending need therefor, be invested in such investments as are specified in Section 22-21-179.

(c) Any such refunding may be effected either by sale of the refunding securities and the application of the proceeds thereof as stated in subsection (b) of this section, or by exchange of the refunding securities for the securities to be refunded thereby or by any combination thereof; provided, that the holders of any securities so to be refunded shall not be compelled without their consent to surrender their securities for payment or exchange prior to the date on which they may be paid or redeemed by call of the corporation under their respective provisions.

(d) All provisions of this article pertaining to securities of the corporation that are not inconsistent with the provisions of this section shall, to the extent applicable, also apply to refunding securities issued by the corporation. The corporation may, at any time, and from time to time, issue securities both for the purpose of no refunding any of its securities and for any other purpose for which it is authorized to issue securities, in which event the provisions of this section respecting refunding securities shall apply only to that portion of such combined issue authorized for refunding purposes and the provisions of this section respecting other financing shall apply to the remaining portion of such combined issue.