Toggling a rail signal multiple times not only changes which rail the lines use, but also bus/tram routes which are near.
Very odd, seems like a bug to me. Why should a rail signal affect road transport’s routes and why are their numerous routes for the same setup?
Compare the turquoise/light blue line, I am ONLY changing the light you can see above the station.
one way rail signal
two way rail signal
One way rail signal
two way rail signal