SDAH NDLS Duronto: দৌঁড়ে চলো , দিল্লি চলো - PPG

This is around PER right?
The whole MAS-AJJ section is automatic signalling territory. In automatic signalling territory, main line trains are allowed to follow each other such that there is at least 150 meter gap between them and with the rear train moving at 10-15 kmph.
In normal block systems, trains are not allowed to skip a signal at Red. In auto-signalling however, the LP can cross a red signal after waiting for one minute (2 minutes in the night), but only...
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at a slow speed (10-15kmph) prepared to stop on a short notice. Even if there is a train ahead, the LP can follow the leading train at a slow speed maintaining a prescribed gap. For EMU's, they can even run with 75 m separation.

That's the beauty of automatic signalling. The train movement is entirely controlled by the track circuits. Between 2 stations, the signals are only controlled by the location of the train.
The controller only gets to decide if a train has to OT another one, and will communicate this to the station masters who control the signals within their station yards. Between stations, the track circuits and axle counters determine the signal aspects ( The controllers can still override these in case of an emergency).
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In an absolute block system, if the LP crosses a signal, the SM's of the stations at either end of the block section need to know this to make sure that no mishaps happen. In an auto-signalling territory, once the train occupies a section, the previous sections' signals will automatically adjust to the presence of the train.
It is not necessary that the LP has to skip the signal, but he has the authority to do so at his personal discretion. There are obviously some restrictions and precautions to be followed though.