Question regarding Atma book fates.

I am a bit late to the party on atma weapons but I want to do them for the fun of it. I really only just started the first book but one of the fates is supposedly a 4 hour long spawn? Giant Seps from the Skyfire 1 book. I literally just missed it as of 5 minutes of typing this, and I've read online that it could take up to 4 hours to respawn. I want to know if this is true because there other things I read stating they reduced the spawn time but I wanted to know so I'm not literally sitting in one spot for 4 hours when I could easily be doing other things from the book >.>.

Nevermind the FATE spawned not to long ago :P.

The Atma books show a lot of problems with the design of progression that was corrected in Heavensward. The problem with the Atma stuff was that the requirements were too specific. The books tend to require 1 rare FATE from what I remember and that is a problem in itself.