[frankly]

Originally Posted by Ken Case

By default, the "Due" perspective groups actions by their due date but doesn't actually sort actions within each group by their individual due dates. If you want to sort actions within a group, you'll need to set the sorting order as well. (You can do this by clicking on the sorting popup in the view bar, or by selecting "Sorting->Due" from the View menu.)

Does that help?

Yep, that did it.