Just out of curiosity, is it even allowed to fly something other than 10s in competition?
The answer is no. However that does not mean the model has not been flown on 12S, mine has a 12S capable ESC, just 'gotta pickup the motor....
Some folks are working to try and have the rules changed about only being able to run 10S batteries in FAI which is supposed to be there for safety. But they have no problem running 12S in the helicopters. The model fly's the current sequences easier with the 12S setup as I think most models would and 5S cells are getting really hard to find these days. I believe the Euro guys, are getting increasingly scared of the electric competition.