After 10 more serves, each player backs up to the endline and repeats 10 more partner serves. Instead of simply catching the serve, have each player pass the serve up to herself, catch it and then serve it back. Setters work on repetition of any particular set. Work fast, Coach, once learned. Drill stops and rotations are made only when the group on the court scores 12 points with full coverage.
Coach stands at net but off-court.
That's 6 players involved in drill. The three players involved in the action move off-court and the other 3 move on for the second attempt. Tips and rolls do NOT count as scores because the goal is to dig and set so well that the attacker has a quality ball to swing at. If your team has less than 12 players, rotate groups. You may choose to leave setters in that position throughout drill.