Oregon Revised Statutes Water Resources: Irrigation, Drainage, Flood Control, Reclamation § 545.631

(1) Before authorizing the issuance of bonds under ORS 545.565 to 545.621, the board of directors shall require that the known holders or their representatives of not less than 80 percent of the total amount of all evidences of indebtedness, whether warrants, bonds or certificates that are to be retired or refunded, shall submit to the board of directors for its acceptance an offer:

(2) The offer shall be in writing and when submitted to the board of directors and accepted by the board, the offer shall be irrevocable until after the board of directors has had the opportunity to authorize the issuance, sale and delivery of refunding bonds to replace and discharge the outstanding indebtedness. Any litigation that is intended to or will restrain or prevent the board of directors from issuing and delivering the refunding bonds shall not subject the offer to revocation until after the litigation is concluded and the board of directors has a reasonable time thereafter in which to issue, sell and deliver the refunding bonds. The offer shall be considered accepted by the board of directors upon delivery of the offer to the board.