Under what condition can track flags be displayed when a track bulletin has been requested?

The correct condition for displaying track flags when a track bulletin has been requested is that it must be verified that the requested track bulletin has been issued. This ensures that all train crews have been adequately informed of any changes, restrictions, or conditions affecting the track before any flags are displayed.

Displaying track flags indicates to operating personnel that there are important updates regarding the track's operational status. If the bulletin has not been officially issued, crews could be left unaware of crucial information, potentially leading to safety issues. Therefore, verifying the issuance of the bulletin ensures that all involved parties are on the same page regarding track safety and condition. This process is vital for maintaining proper communication and operational integrity on the railway network.