Suggestions for NTPs

If you want to move a period, for example from Mo-1 to Tu-3 you can easily do this via drag and drop. However, how do you find out, if it is possible to fill a non-teaching period with an already scheduled lesson?

Click on the position you want to fill in the timetable and hold the left mouse button down for at least two seconds, then move the mouse. Scheduled periods which can be moved to this position will be shown in green.