When does the authority of a Form D line 2 end at a controlled point?

The authority of a Form D line 2 ends at the home signal or controlled point signal. This is crucial because these signals serve as definitive markers that indicate where a train must stop or where its authority is terminated. The home signal is specifically designed to provide guidance on the train's movement into or out of a controlled area, making it the clear endpoint for the Form D authority.

Understanding this point reinforces the importance of signals in railway operations. Signals are not only used to communicate whether a train can proceed, but also to delineate the boundaries of operational authority. This ensures that crews are fully aware of their rights and responsibilities when approaching controlled points, which helps maintain safety and order on the railway system.

For context, while other locations like the last signal before the station, the platform edge, or the station entrance hold significance in train operations, they do not represent the termination point of authority derived from a Form D line 2.