I did a few tests with the lesson planner and I came across the following:
Administration decided to change the start date of term 2 from 07/01/2020 to 14/01/2020. The administrator did’t delete the timetable days assigned to that lost week. We actually never do this. Or should we?
Anyway, the planner’s year view now shows all lessons which are part of that week. This probably shouldn’t happen, I guess.
You could delete the dates to be on the safe side, but they should be ignored by the system once the dates are changed, and thus cause no problems.
In terms of lesson plans, Gibbon is somewhat agnostic when it comes to term time. If you view the planner in Date mode, you cannot view days when Gibbon is closed. But, if you view it in Class mode, then you can add to days that are not school days. The aim here was to give a degree of flexibility (E.g. virtual classes out of term time). In the same way, you can create lesson plans that sit outside timetable classes.
I guess there are reasons to be stricter, but Gibbon, under the rubric of flexibility, tends to be looser with such controls. Part of our small-school heritage as well.
These parameters are up for discussion if the behaviour is causing issues…but yes, it is intended behaviour.