I have a question around the task list management in OX.
Situation:
I make a task in the task list without a reminder but with a start and due date.
I work on this task say 50% done.
When I edit the task the reminder field is empty but the email notification is checked.

My questions:
Does OX send email notifications to the creator and all participants when a due date is missed? When exactly is that? On the same day?
If not how does OX takes care that tasks are not missed? Are the reminders for that? If so it means they have to me set manually?
There is a 15 mins default reminder. Where and how can that be changed?

Any help appreciated