Atma is pretty easy to get now. If you dont get any atmas by the one hour mark of casually fating (instead of try hard-ing to tag every fate in the zone and clearing as fast as possible), start suspecting something is up and change to another zenith weapon or change zones. I recently completed my 3rd set of atma for blm and was using pld to get the atmas. Majority of the atma stones were acquired within 10 fates. The other ones that took me 3+ hours (about 3 of them), I started getting suspicious and switched to another zenith weapon and on 2 of them, I got them on the very next fate. Could all just be coincidence but I'm basically still saying that you can finish 1 atma set in 1 day or less if you wanted to.