Tenn. Code Ann. § 48-58-404: Resignation and removal of officers

(a) An officer may resign at any time by delivering notice to the corporation. A resignation is effective when the notice is effective 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 may fill the pending vacancy before the effective date if the board provides that the successor does not take office until the effective date.

(b) A board may remove any officer at any time with or without cause and any officer or assistant officer, if appointed by another officer, may likewise be removed by such officer.