Specify supervision length
In principle the length of each supervision is automatically taken from the general timetable ('Settings => Time grid').
You can, however, modify these entries manually in order to give a special rating to not particularly pleasant supervision areas and/or breaks or in order to add the missing supervision duration before the first and after the last period.
To do this, simply check the selection box 'Show minutes' (1) in the break supervisions dialogue.
Now select the area for the supervision before the first lesson and enter the value 20 (minutes) (2).
The displayed total of supervision minutes to be scheduled and open changes accordingly from 330 (270) to 390 (300) (3).