I believe that if Surrey Police can prove there is enough regular infringement of speed limits through this monitoring that their plan is to extend average speed limit enforcement to cover the whole stretch from the Burford Bridge roundabout through to the Clarkes Green roundabout and/or possibly also around some or all of the Leatherhead bypass and especially the steep hill section of A24 from Givons Gove roundabout north to the Beaverbrook roundabout.
Hard to know as I see grey vector cameras springing up everywhere in Surrey and elsewhere (clearly very cheap to run) but not so far painted yellow or used for speed enforcement. Police's obsession with tracking only raw speed whiled doing nothing about aggressive driving by people who drive far too close and try to barge others out of the way (usually especially in unbranded white vans or big powerful Mercs in particular as BMW seems to now be old hat for the aggressive psycho driver) is highly frustrating.