NTP if I start on foot at Newton Heath Depot and start a train every signal nearby is red despite no other moving trains near me. Contacting signaller does nothing doesn’t say proceed at restricted speed or denied. Are these trains undrivable ?
I think those are just for decorating the area. Any trains that are allowed onto the line will be in the timetable. Getting on a train not on the timetable (in most cases) will give you an empty service/schedule. So the signal will still at danger permanently.
I mean, if you want to run a red... Run it, save the game, then load the saved game. You’ll be in a glitched service and you can run reds, crash and do all that.