Ron (Houston):

Nice shots thanks Smiley.

My feeling is that this is not a 991 test mule.  To me it looks like a 997.2 special edition like RS (not GT3) or America.  If you notice the little fin (mini spoiler) above the rear window is missing.

Thoughts

 

Ron , here my thoughts :  I believe it's a 991 test mule  ( we know that 991 will have active aerodynamics )

 

mini spoiler

991.jpg

 

          when big wing (duck tail) opens , mini spoiler will slide-up on top of rear glass

           991 spoiler.JPG