Starting with a layout for a hypothetical minimum of 9, I soon realized that it would not be easy. Unfortunately, I had to add three extra cycles in to make everything work properly, but it turned out so close that I don't think too much improvement is possible from here. 11 is probably possible for the pros, 10 might be doable, and I would be extremely surprised if anyone manages 9. I used to dislike production puzzles, but after spending all the time I did getting to know this one, I now absolutely despise production puzzles.