35 Pa. Stat. § 1680.508a
The Commonwealth of Pennsylvania does hereby pledge to and covenant and agree with the holders of any bonds, bond anticipation notes or other obligations issued pursuant to the authority of this act that the Commonwealth will not limit or alter the rights or powers hereby vested in the agency to perform and fulfill the terms of any agreement made with the holders of such bonds, bond anticipation notes or other obligations, or in any way impair the rights or remedies of such holders, until such bonds, bond anticipation notes and other obligations, together with interest thereon, with interest on any unpaid installments of interest, and all costs and expenses in connection with any action or proceedings by or in behalf of such holders, are fully met and discharged or provided for. The agency may include this pledge and agreement of the Commonwealth in any agreement with the holders of bonds, bond anticipation notes and other obligations issued by the agency.
35 P.S. § 1680.508a