It was just recently that Asus rolled out a software update for the Zenfone 3 Deluxe (ZS570KL) but there is in fact another rollout. You can manually check for updates via your system settings. There is not a lot of details other than to say “Improve ZenUI stability”. It’s not clear if this was to squash bugs from the last update.
Version: WW_5.15.44.2562
Date: 2017/7/24
Release Notes: Improve ZenUI stability.
Also Asus has rolled out yet another update for the new Zenfone 4 Max (ZC554KL) phone. The tweaking of the hotspot stability is nice to see.
Version: ZC554KL(8917)_ WW_14.2016.1705.146
Date: 2017/07/19
Release Notes: Fix some minor issues, optimize wifi hotspot stability.
Last but not least, there is an update for the Zenfone Go (ZB552KL) model as well. There are a number of fixes listed.
Version: ZB552KL_ WW_13.0.6.48
Date: 2017/7/24
Release Notes: