'Available now' group is on the bottom of a grouped list

I have set my view to

  • Group by defer date
  • Sort by due date

My problem is that all items that are not deferred (and even might have a due date) are placed on the very bottom of my list. I would expect that those items show up on the top together with all items with a defer dat in the past.
Does anybody agree? Or did I miss a setting?