Sanaa, this is a very good question! It can be very confusing because not only are they all grammatically correct...but they all mean the same thing! If you picture each phrase in your mind, it is the same pucture! You picture the train leaving the station at 10:00 AM the following day. Each phrase implies that the train leaves at a specific future time. However, which phrase you use depends on the rest of your writing around it. Look at the tense form your other sentences in your paragraph use. You must stay with the same form of tense.
I hope this helps!
Linda T., M.Ed.
Reading and English Language Specialist