There in no impossibility to plan a task before current day.
Requested date has no effect on planning : it is only informative.

There in no impossibility to plan a task before current day.

But if I'm creating the task today, I didn't work on this task last friday so the task is late before begin it. :blush:

I don't understand in which case is useful plan a task before current day?

If you define a task that can have been worked on by resource during current week, it may be usefull to plann it fro real start day (and not from current day) if you know that resource has not entere d real work yet.
Now it is just a possibility.
If you ru pllanning calculation with stating date ) today, you won't have this behavior.

Thanks for the clarification.

If I define a starting date with ASAP planification mode, the starting date is just an indication to plan (ie at least the task should be begin at the starting date, but it is possible to plan after depends of priority and disponibility of ressources).