More information in your schedule van be found here: Schedules 

We strongly recommend that you only synchronise courses for which you are officially registered in Osiris. If you manually add the courses before the official registration, it may give incorrect information in your personal Timetables. Programme management registers you for courses several weeks before the course starts. If you still want to know what the timetable will be, you can always type in the course code. However, make sure that you remove the course from your personal Timetables until you know that Programme Management has officially registered you for it.