Ala. Code § 22-23A-10: Refunding Bonds.

The authority may, from time to time, issue and sell its refunding bonds for the purpose of refunding any matured or unmatured bonds of the authority at the time outstanding and any premiums necessary to be paid to redeem any bonds so to be refunded. The holders of such refunding bonds shall be subrogated and entitled to all priorities, rights and pledges to which the bonds refunded thereby were entitled.