It exists in a way, rather differently, the rulebook includes the following;One thing I wondered about, is there still a version of rule 55 on the books today?
"When your train is detained on a running line at a signal at danger, or without a movement authority (MA), you must contact the signaller as soon as possible.
However, you may wait for up to two minutes before contacting the signaller if you can see an obvious reason for the signal being at danger, or not having an MA[,] such as:
• the section ahead being occupied by a train
• a conflicting movement being made."
They don't have to leave the cab and go to the box mind, GSMR has an "SG" button which sends a message to the controlling signaller that there's a train waiting at the signal.