The New "Hunter Derby" Cl?

I was wondering if any of you have heard or know about the new hunter derby cles that are popping up at the A shows. I know in general what they are, but does anyone know if they still judge the horse of style of if they judge it on handiness of the horse, or what? Does it run more like a jumper course with hunter like fences? Im really not sure how the cl is run, or how the riders or scored. But ive seen riders do the course and noticed that alot of great grand-prix riders are in the cl as well with their horses. If someone could explain how this works I would greatly appreciate it! Thanks Alot!