http://www.omnicorse...ulle-power-unit
http://www.formulapa...on-federazione/
According to this sites, Ecclestone told Sky Sports24 HD that Mercedes was in close contact with FIA to define the new engines, and they knew more than the others, that's the reason why they started so strong in 2014 and they still keep that advantage in 2015.
If this is true and is not the Italian media talking BS, I guess we will see a video of the interview.