Was up there on Tuesday and a lot of it seemed shut. It may be possible to do more than I did if you know your way round but the diversion does seem to miss out a fair chunk on the way down.
Seemed like it was the stuff around magic mushroom and pie run and it made the loop very short althogh my memory of the place is sketchy as it all blurrs into one.
THe diversion is hilarious if you like muddy as it was damp when I was there and cut up. Sliding all over the place but enough gradient to keep your speed up.
I think there are better details on the site regarding post numbers etc. I was doing a long ride anyway so wasn’t that bothered about loosing a few km.