Any certification or endorsement of consent made by the local finance board or by a majority of the members thereof or by the secretary thereof pursuant to its direction as to any issue of refunding bonds shall, after the issuance of such refunding bonds in reliance thereon, be conclusive as to its validity or regularity and shall not be contested in any action or proceeding relating to such refunding bonds instituted after the issuance of such bonds.
The county, municipality or school district may enter into any contracts or agreements to implement the refunding program, including agreements with banking institutions with respect to the application of moneys deposited in a sinking fund for the payment of the refunding bonds at their maturity date to the purchase of obligations of the United States Government or obligations the principal of and interest on which are guaranteed by the United States Government or obligations of any agency or instrumentality of the United States Government without regard to any limitations as to the investment or deposit of moneys.
N.J.S. § 18A:24-61.5