Information: Changes to the date (and not only the switching time) can only be
made in the first entry for this date and always apply to all entries for this day.
The yearly calendar is sorted, i.e. an older date is put before a more recent date.
10.5.8.2 Menu 5.7.1: Copying a day in the yearly calendar
All entries for a certain day can be copied to another day with a different date on the yearly calendar.
However, a new date has to be entered for this.
Menu Action Display reading Explanation