Ala. Code § 11-15-14
All or any warrants issued by the corporation may from time to time thereafter be refunded by the issuance of refunding revenue warrants of the corporation, but the amount of any refunding warrants so issued shall not exceed the principal of the warrants refunded thereby together with any unpaid interest thereon and any premiums, commissions and expenses necessary to be paid in connection with such refunding. Any such refunding may be done regardless of whether the warrants to be refunded shall have then matured or shall thereafter mature and may be effected either by sale of the refunding warrants and the application of the proceeds thereof or by exchange of the refunding warrants for the warrants to be refunded thereby; provided, that the holders of any warrants so to be refunded shall not be compelled without their consent to surrender their warrants for payment or exchange prior to the date on which they may be redeemed by the corporation under their provisions. Any refunding warrants of the corporation shall be payable solely from the revenues out of which warrants to be refunded thereby were payable.
Ala. Code § 11-15-14 (1975)