What is not allowed with a Form D line 2 in both directions?

In the context of Form D line 2, the restriction on additional line 2 authorities in both directions is rooted in the fundamental purpose of maintaining clear and effective communication and authority over train movements. When a Form D line 2 has been issued, it provides specific instructions and authority for certain trains to move in a designated area. Allowing additional line 2 authorities in both directions would create conflicts and confusion regarding which train has the right of way, compromising safety and operational clarity.

By ensuring that no additional line 2 authorities can be issued in both directions, the protocol helps prevent overcrowding of the authority system and minimizes the risk of potential accidents or miscommunications on the railway. This focus on safety and coordination is vital for securing the orderly functioning of train operations.

While cancellations of existing authorities, issuing a new Form D, and extending authority to other trains can be managed through proper protocols and procedures, introducing additional line 2 authorities risks undermining the integrity of the existing authority structure and the safety measures surrounding train operations.