Thought I'd report back since I believe I have the same rifle as you - DTA with factory 6.5 Creedmoor conversion. I've attached two sets of target - one with the 143 Gr ELD-X and one with the 147 Gr ELD-M - both using Reloader 17. You will notice that both loads group just alright until specific nodes then tighten WAY up before spreading back out again. I never ran into any pressure signs on brass, primers, or bolt lift with any loads BUT this is my rifle, at my elevation, under my conditions.
One interesting thing of note is that my Extreme spread tightened up dramatically with the accuracy nodes. Not always the case with my rifles, but appears to be a pattern with this one and RL17.
I've settled on 41.3 Gr for the 143s and 40.6 Gr for the 147s.
Interestingly enough - both of these loads reach 1760 yards at my DA traveling at 1120 and 1170 fps, respectively but the slower 147s reach the target a tick quicker. I will likely bump the powder charge a bit on both of them just to see if there is a higher accuracy node...but then again, why waste powder, bullets, brass life, time, etc when I could just be hammering steel at a mile with the loads I already have?