Hi folks,
I wish that I knew how they improved the drag (coefficient?) by 9% -- I traced their image of the old and new sections:
...and the new section is ~8% LARGER, so the drag improvement probably comes from a better overall shape (the tail may be longer, and the nose has changed, and the section shape (and size) has changed, and the windshield had changed, and the side windows have changed (and they also now roll down), and the width of the front wheels has been narrowed (down to ~7' from ~7'-8") and the wheel pods have made smaller and they are now asymmetrical (the inside face is flatter, and the outside curves more -- this may have improved the interaction of the air flows around them and the main body?). The ground clearance has been increased (which would likely help the drag).
Another major functional improvement of the production version, is that the doors open up more and get more out of the way -- so we do not whack our heads getting in. This was a complaint of many people; not just the tall ones.
I myself am 6'-4" and ~230 pounds, so I am very glad they increased the interior space. Some of the folks on the Aptera forum who have actually sat in the older versions, who are close to my height have commented on this improvement.