What must the facility delivering a void time to a pilot issue as well?

When a facility delivers a void time to a pilot, it must also issue a time check. This is crucial for maintaining situational awareness and ensuring that the pilot has the correct time reference, as the void time indicates when the clearance is no longer valid. Providing the time check helps prevent misunderstandings regarding the timing and allows the pilot to effectively manage their flight plan accordingly.

In the context of air traffic control, void times are often used when issuing clearances for departures, allowing pilots to understand the timeframe in which they must depart. A time check, concurrently provided with the void time, reinforces the importance of coordination and timing within air traffic management.

The other options, while relevant in various contexts of flight operations and air traffic control, do not specifically relate to the issuance of a void time. An altitude check focuses on verifying the aircraft's altitude rather than timing, a departure confirmation involves acknowledging a departure clearance rather than the timing aspect, and a clearance revision pertains to modifications of previously issued clearances. None of these provide the immediate and critical timing information that a time check does in conjunction with a void time.