Oregon Revised Statutes Corporations and Partnerships § 65.381

(1) An officer may resign at any time by delivering notice to the corporation. A resignation is effective when the notice is effective under ORS 65.034 unless the notice specifies a later effective date. If a resignation is made effective at a later date and the corporation accepts the later effective date, its board of directors or any other person as authorized under the articles or bylaws may fill the pending vacancy before the effective date if the board or any other person provides that the successor does not take office until the effective date.

(2) A board of directors or any other person authorized under the articles or bylaws to elect or appoint an officer may remove any officer the board or any other person is entitled to elect or appoint, at any time with or without cause.

(3) Once delivered, a notice of resignation is irrevocable unless revocation is permitted by the board of directors.