A batch can be assigned to an existing timetable only if weekdays and class timings sets have been created for the batch. Similarly, a batch can be unassigned from a timetable only if subject entries have not been created in the timetable for that batch.
At the top of your dashboard, click the module access icon > Academics > Timetable > Edit Timetable to open the Edit Timetable page.
Click Edit range beside the timetable you want to edit.
In the top right, click the Manage timetable button to open the Manage timetable page. Previously assigned batches are listed on the left under Assigned Batches, and the new batches are listed on the right under Available Batches.
Select the batches you want to assign a timetable and use the arrow to move the selected batches from the Available Batches list to the Assigned Batches list
To unassign select the batches you want to un-assign the timetable and use the arrow to move the selected batches from the Assigned Batches list to the Available Batches list.
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