Interesting timeline...June 2016 is when pilot production of the 950A program commences, thus the first non-prototype builds of the LC. Series production ramps up in December. Have they even disclosed where production will take place? Old LFA factory in Motomachi or Tahara?
The non-camouflaged LCs shown since Detroit and from November 2015 photoshoots, were of the last prototyping stage, where many production items are incorporated into the vehicles for final testing. I don't know Toyota calls these, but I refer to them as "final evaluation vehicles".
Before that stage starts, everything must be dead final, in terms of smaller details like trim and packaging.
The cars seen last summer were more rudimentary, but utilised the production design, which was frozen by mid-2014. I am not entirely aware of Toyota's prototype gestation period from design freeze, as at some OEMS it can be as little as 4 months and as long as 18 months.
The first final LC design wearing 950A prototypes might have been assembled in December 2014 for Hokkaido testing, going LHD in the summer of 2015.