I killed a bunch of lvl 29 water sprites during fog, but Anapos didn't spawn until 56 minutes (ET) into the next weather cycle (heatwaves). Repeated this in another instance and it spawned 1hr 24 minutes into the next weather cycle (blizzards). Decided to keep track of kills for the third try. About 72 sprites were killed during the fog window, but there was no spawn after (storms). Waited until the next fog window (occurred 5 cycles after the previous fog started, or 1hr 55 minutes later) in the same instance and killed 47 more. It then spawned 2hr 7 minutes into the next cycle (storms). When it spawned, the duty timer had about 26:30 left and it didn't spawn in the 153:30 before that.

Got into what looked like a fresh instance since both elemental conflicts had just started and the players there the longest had only been in for 10 minutes. Anapos spawned during fog after about 62 kills.

There are also the Louhi daytime spawns to consider. Using Anemos logic, the required number of mobs had already been killed and it was only Louhi spawning once his cd was up, but we're also hearing it takes most of a lockout or a bazillion kills to spawn him. Both can't be right unless Louhi's cd is longer than two hours.