Oregon Revised Statutes Public Borrowing § 287A.360

(1) In addition to any other authority to issue refunding bonds, a public body may issue current refunding bonds to refund or purchase its outstanding bonds.

(2) A public body may secure current refunding bonds with any of the revenues and covenants that the public body could have used to secure the refunded or purchased bonds under the law in effect when the refunded or purchased bonds were issued and with revenues and covenants that the public body could have used to secure the refunded or purchased bonds if the laws that are in effect when the current refunding bonds are issued were in effect when the refunded or purchased bonds were issued.

(3) A public body may authorize current refunding bonds by resolution or ordinance without complying with the procedural requirements that applied to the refunded or purchased bonds, including issuing:

(4) The maturities of current refunding bonds authorized by this section may not exceed by more than six months: