What should the pilot do if their departure time differs by more than 3 minutes from the assumed departure time?

When a pilot's departure time differs by more than 3 minutes from the assumed departure time, reporting the actual departure time is crucial. This ensures that air traffic control (ATC) and other relevant personnel have the most current information about the flight's status, which is essential for maintaining safety and coordination in air traffic management. Accurate reporting allows ATC to adjust flight sequencing, manage airport traffic, and ensure that other flights are informed of any potential delays or changes.

Updating the flight plan, while important in certain contexts, may not be necessary if the only change is a slightly different departure time. Similarly, contacting the control center immediately may be excessive unless there are significant operational changes or safety concerns. Continuing without notifying ATC can lead to miscommunication and could jeopardize safety, making it imperative to report the actual departure time to keep everyone informed and safe.