I recently purchased a Nerve AM 8.0X and had the same issue. When the seat post was compressed, the cable stuck right out in the way, so I played around with routing the cable and found a perfect fit; try routing the cable from under the top tube out to the left side (when looking from above), then up over the top tube to the right-hand side and then around the back of the seat post and up into the reverb cable tidy thing which I put on the left-hand side, in-line with the seat post barb and cable-tied it to the reverb itself (just below the silver bit).
When the post is extended fully, the cable isn’t too tight (some cable rub patches strategically placed is a good idea!), and when dropped, the cable hardly sticks out at all!
Hope this makes sense…