2021 320S What are these cutouts for?

Can anyone help me figure out what these cutouts are for?  They are in both rear leg supports for the pullout slats for the seat cushions when you make the bed.  Do all 2021 320s have these?  Does it have anything to do with air flow for the Alde heating system?  I have the horizontal openings near the floor and above it for air flow to the Alde heat exchangers.  Should there be a corresponding opening in the plywood behind the cutouts for additional airflow?  Are these cutouts left over from a previous model and they made the cutouts just because they did it before? 

There is plenty of clearance for the air conditioning duct on the passenger side even without the cutout and the cutout is not quite positioned correctly for this anyway.  There is no ducting on the driver's side.  

I've just been scratching my head on why these are there.  They don't seem to serve any purpose as they are and the edges sometimes catch on the back bench cushion when you raise the slats to access storage underneath.    Thanks for any thoughts!