I just Googled Bat wing awning and found the "birds eye" view of it.
I can imagine an additional panel that would be attached to the 240cm side as a right triangle.
Then the awning would run the whole length of the left side of the Van as seen from the air. It would require another
tent pole but it may be nice to have just the same.
I do like the idea of a wrap around awning, as you can move around the Van during the day
as the Sun passes over. Thus you can always find some shade.
I like this idea very much, and can imagine it easily attached to a pair of ladder racks as an add on.
When folded up the awning could then be stowed in a heavy canvas bag and the front left post
of the ladder rack could have a bracket that would hold the 4 horizontal poles of the "Bat wing"
fast and safe while the Van is traveling.
The racks could also carry plastic pipe set up as a water tanks, solar panels, and so forth.
I've long considered 2 or more ladder racks on the roof of a Van for such functions as awnings,
water tanks, luggage-cargo, and just freeing up room inside the Van where possible. My first Van's
were not high tops so roof racks just seemed an obvious solution.