In the Hauptstrecke Hamburg - Lübeck Preview Stream that was run this morning (my time, evening UK) the freight had to wait about 10 minutes or so for another service which is a good thing to build into the game because it is realistic. However 10 minutes is a very long wait for a game player when there isn't much to do. Some games where this sort of thing happen include a time travel concept where the player can either choose to sit and wait or they can speed up time to experience the entire wait but under a fast clock so its a shorter wait in real time.
I think this is a great idea. It could also be used when a train finishes a service and you have to wait for the next one to begin. Would love to see this implemented!