On the 2021 Rapid Transit timetable, S6 has issues at both ends of the line. At the southern end, there is only the first unit of an AI train actually in the station, so the stop marker isn’t far enough. More worryingly, at the Leipzig-Messe end, it’s not actually possible to complete a timetabled service, as the stop marker at the shunthead is 3m too far, in the buffers, therefore the services are unplayable as you can go all the way down the line and then not be able to complete the journey.
