Remember, I did this study in 2010. I CFR'd in 2015 and retired in 2018 so my contact with the CWO world is fading in the rearview mirror.
There were, as I recall, 591 CPO1/CWOs. Not all were in CPO1/CWO positions. There were, I believe, almost three dozen Chiefs in over/under ranked positions, which was part of the problem. This was at the time when the P Res was attempting to create more SA/KP, mostly in the Army, but the CFCWO (Cleroux, I think) wanted to get a better grip on the population as a whole before these positions went forward for approval. Overlay PRECS on top of this and there was an appetite for culling the herd.