CLEARANCE VOID IF NOT OFF BY (TIME)
Pilot/Controller Glossary with JO 7110.65BB, Change 3, effective July 9, 2026 · Official text on faa.gov
Used by ATC to advise an aircraft that the departure release is automatically canceled if takeoff is not made prior to a specified time. The expiration of a clearance void time does not cancel the departure clearance or IFR flight plan. It withdraws the pilot's authority to depart IFR until a new departure release/release time has been issued by ATC. Pilots who choose to depart VFR after their clearance void time has expired should not depart using the previously assigned IFR transponder code.