That is nice. Manzi did great with recall, but I had the opposite problem. I would call him and he would come, but I learned that the real signal was my arm, not the whistle or call. Thus, if he was out of sight and didn't see my arm, even when I called he wouldn't come. This is a problem when free flying because often they will be high up in a tree or just out of view and not able to see your arm.
Later, I worked with him to come when I was around a corner and he didn't see my arm. Now he is pretty good about that and knows that as soon as he rounds the corner, he needs to be looking around to see where I am and how to land on my arm. That panicked him at first, but now he is an expert.