Lesson unavailable periods

You can mark specific time slots during which a particular lesson should not be scheduled. This is useful when a lesson has a fixed constraint that applies only to it — not to the teacher or class in general.

Go to Lessons, open a lesson for editing, and expand the Periods of unavailability section.

Two types of markers

Block (Strict) — shown in red. The scheduler will never place this lesson in this slot.

Avoid (Flexible) — shown in yellow. The scheduler will try to avoid this slot but may use it if there is no other option.

Blocked slots

Some slots in the table may already appear as blocked (greyed out). These are slots that are unavailable due to constraints set on the teacher or the class assigned to this lesson — for example, the teacher marked as unavailable on Monday morning, or the class configured not to have lessons after 13:00.

How to mark slots

1. Select a marker tool: Block (Strict) or Avoid (Flexible).
2. Click on individual cells in the table, or click and drag to mark multiple slots at once.
3. Click on a day label (row header) to mark the entire day.
4. Click on a time slot label (column header) to mark that time across all days.

To remove a marker, select the same tool and click the marked cell again, or use Reset all to clear the entire table.

Recommendation

Use Avoid (Flexible) wherever possible. If the constraint applies to all lessons of a teacher, set it on the teacher instead. If it applies to all lessons of a class, set it on the class instead.

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