Some time ago, the way the timetable worked was changed. Before the change, the duration of the task and its start and due dates could be set separately.
How is it now possible to change the start or due date without overwriting the time immediately?
Example:
I want to reschedule a task whose duration is set to one hour to tomorrow.

When I "intuitively" try to change the date, no matter how I try, the duration is always "rounded" to the whole day.