This scenario works just fine for about 10 minutes. Right before the first stop, I got stuck at a red signal because there was a Class 166 service on my track that refused to move for 5 minutes, obviously making me late for the first stop. However, I believe that I had followed this service since the beginning of the scenario and it has seemingly just stopped and changed direction. HELP!!! (Here are some pictures.)
I think I've had the same Issue bit I'm not quite sure. Normally it works when you restart the scenario or the second possibility, on the scenario are 3 services featured, maybe switch to another one and after completing that try the service again were you had the Issue. I hope this helps.