Go to Activity button

Find the activity you want to change.

Change one row/lesson at a time

In this example we will change the top lesson from 12.00-12.45 to 12.30-13.15.

Activity lesson 1

Click into the fields, remove both weekdays and change the times accordingly.

Activity lesson 2

Click outside the blue marking and you're done.

Activity lesson 3

Continue with the rest of the lessons where applicable.

Please note that 'Perpetual exclude' is automatically set on lessons you change.