I'm currently looking to yoink a Blade of the Poisoned Mind from one of the several caches for the Lost and Found Achievement. However, I'm shooting in the dark in my camping as I don't know when it'll show up.
The comments on Wowhead are of very little help, with some merely saying that it might have something to do with server restarts, and others discounting that possibility.
What is the actual respawn window for Lost and Found treasures? A couple of hours? Days? Something else?