How are freight trains scheduled?

Some goods trains are run as pre-scheduled or timetabled services (Link and Crack trains, Quick Transit Service, etc.). The majority of goods trains, however, are run as requirements arise. The process of arranging for a goods train to run is known as ordering a goods train. Ordering a goods train involves the issuance of written advice to the yard or station and loco shed that a certain train will run, starting from the station or yard at a certain time and running to a certain schedule. The written advice is known as the Train Notice. The train notice is normally issued at least 3 hours before the advertised departure of the train, so that the rake can be marshalled and the locomotives prepared for the trip. Once the train departs, it is under the control of the section controllers until it reaches the next goods yard (where the next section controller picks it up). Apart from coordinating with station staff for through running on the main or loop lines, normally goods trains run without attention from station staff.

Source - IFRCA.org