When is an extra train allowed to operate without a running order under rule 251 on multiple tracks?

An extra train is allowed to operate without a running order under rule 251 on multiple tracks when it has proper signal indication or the permission of the block operator. This is essential for maintaining safety and coordination on the rail network. Proper signal indications ensure that trains are informed about safe movement into blocks that are clear of other trains, and the block operator serves as a crucial communication link, providing authorization and managing train movements.

The proper signal indication or permission from the block operator guarantees that the train proceeds only when it is safe to do so, aligning with the operational standards required to prevent collisions or other safety incidents. This reflects the principle that trained personnel must confirm safety protocols are met before any movement occurs, which is vital in a system that often manages multiple trains simultaneously on various tracks.