Great weather at Nurburgring-why aren't the Corvette C7 Stingray and C7 Z06 there to set lap times?

When in September of 2014, +Tadge Juechter refused to disclose the lap time for the Stingray, it was supposedly due to rain during testing.

Well, the weather has been great at Nurburgring, why aren't the new Corvettes there,  scoring very impressive lap times?

The times must be impressive since according to Tadge, the new Z06 is faster than the last ZR1.  Since C6 ZR1 performance portfolio included a very impressive Nurburgring lap time, is this another instance when Juechter's claims should be taken on faith?

Come on Tadge, it has not been raining for quite a while.