the way i thought of it is he summons them one at a time, but he can only summon 6 inside the three turns, so from the moment he fires off the first one for that post and the two after he only has 5 more, but they don't all come back together.

say he fires one the first post, then none in the second, then two in the third. on the fourth post he only gets the first one back meaning four arrows that he can use. he wont have the other two back till the sixth post.

so while he has a limit of how many he can fire in all, each one has it's own cooldown that starts when it's fired. so, for my next post i only have one arrow left, then the turn after that i get two back, meaning i will have either two or three depending on if i use that last one in my next turn

does that make sense?

and i'll add a post or two cooldown, i use it so rarely, and normally as part of an attack, that it shouldn't matter to much other than dealing with some of the 'trust me' thing.