How to set exact date to change the week or the term in published timetable

In ASC Timetables online you can specify the exact date for change of the week, term or just change the timetable in one day to another day. This change will be then taken into the classregister and the substitution.
1. Select the timetable
2. Click on "Properties" button.
3. Use "Add change" button
4. In the new dialog you can set the date from the school year, the object you wish to change (day, week or term) and then the new value. Confirm this change by "OK".