What must happen before a train that is relieved from inspection can proceed?

Before a train that has been relieved from inspection can proceed, it is required to notify the Help Desk. This step is essential because it ensures that all relevant personnel are updated about the status of the train and can communicate any necessary information regarding its movement. The notification helps maintain safety standards and operational efficiency, as it allows for proper monitoring of the train's journey.

In this context, the process of informing the Help Desk serves as a critical point of communication that aids in risk management and ensures compliance with operational protocols. The other options might imply actions that do not align with procedure or are unnecessary in this context.