How may a train that passes beyond the limits of an automatic block where Rule 261 is in effect, re-enter that block?

In scenarios where Rule 261 is in effect, a train that has passed beyond the limits of an automatic block must re-enter that block with permission from the train dispatcher. This protocol is essential for maintaining safe operations within the signaling system, ensuring that all movements are controlled and coordinated.

When a train moves beyond an automatic block, it may be in a situation where the line ahead is occupied or where there may be potential conflicts with other trains. By requiring permission from the train dispatcher, the system ensures that the dispatcher has full oversight of the train's movements and can manage the traffic flow accordingly. This process helps to prevent accidents and ensures that all safety protocols are adhered to before allowing the train to re-enter the block.

Other options, such as using a hand signal or manual switch operations, do not provide the centralized oversight for safe re-entry into an automatic signaling system. Reversing the train's direction without proper authority could lead to unsafe situations on the tracks. Hence, obtaining permission from the train dispatcher is the correct method for ensuring safety and compliance with operational rules.