(a) Presumption.--Bonds reciting in substance that they have been issued by the authority to accomplish the public purposes of this chapter shall be conclusively deemed in any suit, action or proceeding involving the validity or enforceability of the bonds or their security to have been issued for the public purposes of this chapter.
(b) Estoppel.--After issuance, bonds shall be conclusively presumed to be fully authorized and issued under the laws of this Commonwealth, and any person shall be estopped from questioning their validity, sale, execution or delivery by the authority.