I think there has been a change of design fairly recently (within the last year perhaps).
Our Cali, which was built in June 2014, originally had folding battens located at the mid-point of the panels, i.e sitting over the mesh windows. The battens weren't sewn for their full length to allow the zips to be undone and the semi-circular canvas over the mesh to be pulled down. However, this allowed billowing of the canvas during closing.
After a workshop error at the the VW dealer's, which resulted in a tear in the canvas, the dealer fitted new bellows in March 2015. These have two battens either side of the semi-circular panels and these are sewn for their full length (like your pictures above). This is a much better design and hopefully will eliminate billowing.
Unlike Tomtomman65 (above) I still keep my bungee on because IMO it helps make a neater job of folding in the front part of the canvas above the sliding roof panel.