I think you were pretty close back in April....

Believe they are indeed 'supplementary' flight control surfaces. The
aircraft appears to be at a relatively high AOA based on the leading edge
devices. Coupled with the rather significant deflection of the 'rudders'
and 'ailerons' it seems that we're seeing a picture of the aircraft in a
fairly high performance posture (roll to the right?). This is the first
picture I have seen of aircraft in a slow speed, maneuvering situation and
also first picture of the 'smurfs' deployed. Just coincidence??

Just a guess....

Mark


Not coincidence but not flight control surfaces either.