Schlumpf High Speed Drive Version #2
 

I've read in numerous places on the net that refer to a second version of Schlumpf's HSD that has a 34T chainwheel that brings this drive into compliance with the NuVinci hub.
However, Schlumpf won't talk about it yet it's being used by a number of bike retailers that charge $100 more for this version.
That leaves me with the impression that perhaps the retailers are themselves modifying the drive.
Can anyone enlighten me and also tell me just what the modification involves?