And then you need to subtract the cars that don't have the "Enhanced Autopilot" option. I assume that they won't be among the 1000 cars getting the AP2 features in the update.
No, they need to include some non-EAP cars as well to make sure it works on them as well. Though I suppose that they could do that field testing later and roll the update out to them later more in line with the 8.1 update for AP HW1 cars.