What is the difference between the Task Start and Due Date and Recurrence End Date?

Note that the below instructions apply only to users with the permission to view, create, update, and/or delete Tasks.

When you add or edit a Task, you can set a "Start Date" and "Due Date" (incl time) for when you want the Assigned user to complete the Task by. If the Task is not completed by that "Due Date", the Task Status automatically changes to 'Overdue' (unless it was set to On Hold or At Risk) with a Task Status change notification sent out to all users involved.

If you decide to make the Task recurring, it will also give you an option to add a "Recurrence End Date" (incl time) via the Custom option. "Recurrence End Date" is for any temporary or seasonal recurring tasks so you can set a future date for when the recurring stops.