Brian,
All units sold in the US have not had this upgrade unless its been done at specific request. If you've not got it yet, just have it changed prior to shipment.

Yes, absolutely the upgrade is free. And all 9Cs in for any type of servie in the future will receive this upgrade for free, even though a huge percentage of 9C users will never utilize the combination of features which causes this problem to appear.

If you want to be sure your radio needs an update, go into a glid2 model, set up butterfly AND elevator compensation in butterfly AND v-tail. now go to the servo screen, and give butterfly inputs. You will see half the volume of travel on the rudder servo than the elevator servo. You can fix this with a simple mix, or you can have the processor upgraded at no charge.