Yes Lezzare is correct. The mechanic will tell you the same thing. They hook it up to a machine where it pulls the dirty fluid out and replaces it with fresh ATF via the tranny oil lines. But theres no way around it, you still need to pay for 10+ litres of ATF. (The 40% thing refers to only draining the pan once)
Sorry mate, but if you wanna do it right, you gotta pay up! But once its done its good for at least 60,000km with Transmax Z so its not so bad in the long run.
Even if they magically can remove it all, the trans holds over 7 Liters so you'll still be up for at least 2 bottles. But it doesnt work like that hehe.