Voluntary surrender or limitation on maturity; limitation on principal, interest and maturity

1. No bonds may be refunded under this chapter unless the holders of those bonds voluntarily surrender them for exchange or payment, or unless they either mature or are callable for prior redemption under their terms within 25 years from the date of issuance of the refunding bonds. Provision must be made for paying the bonds within that period. 2. The maturity of any bond refunded may not be extended beyond 25 years, or beyond 1 year next following the date of the last outstanding maturity, whichever is later, nor may any interest on any bond refunded be increased to any rate which exceeds by more than 5 percent the Index of Revenue Bonds which was most recently published before bids are received or a negotiated offer for the bonds is accepted. 3. The principal amount of the refunding bonds may exceed, be less than or equal to the principal amount of the refunded bonds, if sufficient provision is made for their payment.