In my current city I started seeing outgoing train traffic backing up outside the city. Using mods to look outside the city area, I found the problem. At the outside connection, there are incoming trains on both tracks. They take turns moving on to the inbound track, with a new train appearing as soon as one bases the crossover point. The outgoing trains can't ever reach the edge of the map because that section of track is always occupied by an incoming train. Does anyone know if there's a way to fix this?