The front wing is a sign of the Wren mod.
It featured the “Wren’s teeth” on the wing (which is what I believe are the fences you’re refrerring to) which were anti-adverse-yaw swiveling plates, double -slotted flaps and drooped ailerons.

The canard’s elevator was mechanically linked to the regular elevator for greater control at low landing speeds.

A later version offered a special Hartell prop with a 5 degree low-pitch stop with Beta control.
Cessna engineer/test pilot William D. Thompson said that he estimated that you could get 90% of what the package offered with just the prop alone.