This workout looks like it would be a solid 12 AMRAP, guessing now I’d say around 8 rounds for advanced and 6 novice would be good scores.
A workout with a high volume of squatting and box jumps most often comes down to your ability to cycle box jumps efficiently, the most efficient way to do this is to rely mostly on the foot and ankle complex to spring back off the ground on the rebound. Most people though rely on more a quad based shallow knee and hip extension to jump back on to the box.
That jumping versus relying on the lower leg taxes the already taxed quads much more. This will lead the endurance of yours being the limiting factor for performance instead of it being cardiac output ability