RAF Atlas C.1 – airflow delector

This recent photo of ZM400 shows it fitted with a scabbed-on airflow deflector in front of the rear paratroop exit door.

Is this a new fitment on trial ??

I thought that the inner and outer props rotating in opposite directions was supposed to provide a benign airflow for paradropping ??

Maybe the airflow isn’t as smooth as was expected ???

Ken