Advisor - Lessons of different length
The software allows you to input double and single lessons of the same subjects.
However sometimes it may be preferable to input them all as single lessons.
For example if you have 5 lesson per week you may have one double lesson (2+1+1+1) or two double lessons (2+2+1).
If both situations are ok for your school, then it is better to leave the decision on the generation. Maybe it will then be possible to find a better schedule if it has more options. This can be especially true if you have many such lessons. Because if you define them all as 2+2+1 - such a timetable might not even exist, but if you allow the software to go for 2+1+1+1 it may find a solution. Once you have a solution, you can try to go back to 2+2+1 for certain subjects where it is more preferable to have double lessons.
Please check:
I want to have 1+1+1+2 OR 1+2+2 lessons per week.