I have noticed at times,if I was generating the timetables and then decide to remove some constraints by first stopping,the time spent on regenerating increases.At times the time is longer than the previous one when the constraints were not removed.How do I solve this?
Usually, less constraints means easier. But sometimes the constraints help the generation (think of a locked timetable, which generates instantly).
Is your timetable still solving? (even if a bit slower.) If so, it is OK.