Hate to ask such a mundane question, but I'm getting conflicting answers via google. We had a one day test drive of a Model S (I'm now waiting for delivery on a new inventory S), and I know there were 2 cup holders built-in under the sliding armrest. I believe there were 2 additional 'insertable' cup holders in the forward center compartment that were not installed. So is this the now standard configuration with 2 also in the rear under the AC vent? Color me confused.