The corporate authorities of any municipality, without submitting the question to the electors thereof for approval, may authorize by ordinance the issuance of refunding bonds (1) to refund its bonds prior to their maturity; (2) to refund its unpaid matured bonds; (3) to refund matured coupons evidencing interest upon its unpaid bonds; (4) to refund interest at the coupon rate upon its unpaid matured bonds that has accrued since the maturity of these bonds; and (5) to refund its bonds which by their terms are subject to redemption before maturity.
     The refunding bonds may be made registerable as to principal and may bear interest at a rate not to exceed the maximum rate authorized by the Bond Authorization Act, as amended at the time of the making of the contract, payable at such time and place as may be provided in the bond ordinance.
     The refunding bonds shall remain valid even though one or more of the officers executing the bonds cease to hold his or their offices before the bonds are delivered.
     With respect to instruments for the payment of money issued under this Section either before, on, or after the effective date of this amendatory Act of 1989, it is and always has been the intention of the General Assembly (i) that the Omnibus Bond Acts are and always have been supplementary grants of power to issue instruments in accordance with the Omnibus Bond Acts, regardless of any provision of this Act that may appear to be or to have been more restrictive than those Acts, (ii) that the provisions of this Section are not a limitation on the supplementary authority granted by the Omnibus Bond Acts, and (iii) that instruments issued under this Section within the supplementary authority granted by the Omnibus Bond Acts are not invalid because of any provision of this Act that may appear to be or to have been more restrictive than those Acts.
     The amendatory Acts of 1971, 1972 and 1973 are not a limit upon any municipality which is a home rule unit.