I’ve just tested again and the behaviour is definitely that the line gets assigned to a platform when you add the station. If you have a two platform station and add it to two lines they will each get their own platform, assuming they’re both equally reachable and not one-way etc.
I guess this is working as intended from a dev perspective. We won’t get to pick which platform is used until we get waypoints. I see the advantages over TTD behaviour for preventing bunching with this approach, so it’s interesting. I wanted a TTD-like game, not TTD in 3D so I’m personally happy to have something new. Others will have other opinions.
What I would like eventually is a way of overriding this behaviour, even temporarily. Occasionally on my commute I have to move platforms because some issue is causing the controller to move trains to another line to keep things moving. We may need that too.
I also wonder if this is why we don’t have pre-signals. If the line paths are all pre-determined a train will always pick the same pathway through a complex branching of junctions – there’s never a choice. I guess the one thing I really don’t like about this is that I like setting up the network and watching how it unfolds when the trains have to make these choices, and it looks like we don’t have that mechanic here.