I think it's different subframes, their bike (short alloy mono subframe) and the bip subframe result in slight differences. Also, it may be that later models or even R's have a slightly longer Ride Height Adjuster (although I doubt it.)
This is why a proper tools desirable, as it's correct regardless of subframe etc.
Also, remember that Section8 are a race team and may want a much more aggressive geometry over that recommended by Ducati. Also, be careful not to wind the ride height adjuster out too far, or it'll be weak as theirs insufficient threads in the rod to hold it together.
If you've set the RHA to 261mm, leave it there for now and see how it feels, then order one of Harv's RH Tools so you can get a proper check on it.
Threaded Mode