I was asked by another person if there is a schedule for the trains going to Oswego and back
No. There's no set schedule beyond the time whatever local is running up there goes on duty. I don't know that they even have one in Fulton anymore, or if it's based at Woodard now. They go up whenever their cars are drilled and put together, switch as needed, then return.
Now probably you can estimate because they likely do the same work regularly. Probably the best guy to ask when they go by is Paul. You can just about see them from his house.