You can undo and redo your changes by using menu View or using buttons on the toolbar:
Please note that this only affects the positions of the cards. It is not possible to Undo changes in the contracts.
A good idea is also to use File/Save as... to save the timetable on disk under different name. That will allow you to store a semi-finished version of the timetable, to which you can return in the future.
This article was viewed 88918 times.51187 / 88918