thats your preload adjustment. shock length will be done via the bottom connection,but dont think it can be done on the o/e shock (could be wrong,just dont remember any adjustment there)
anyway,easiest way to remove rear shock is as Alex says,remove bottom subframe bolts,loosen top and pivot up but it is a work around as is quite fiddly.if time allows,remove tank etc for more room.
Flipping the eccentric on it's own is worth doing - if you have an abba-type stand then you don't have to remove anything apart from the bolt although it is a bit fiddly to do.
Flipping the eccentric suspension mount has made the bike even easier to throw in and out of the corners, I'm impressed how much different and better it feels.
Cheers for the recommendation.
Just had a blast up to Hawes from Morecambe via Ingleton where there are some cracking roads to test it on and I'm just much more confident with the bike than before and I didn't think I could be [emoji23]
I ended up doing 110 miles just because I could, after Hawes I headed for Kirkby Stephen - Tebay - Kendal - Sedbergh - Devil's bridge - Back home, awesome ride.