I find it odd that those on 18E226 are not being prompted to update. I downloaded the installer and now I am on 18E227 on MacBook Air 2017.
Gatekeeper was 165 and XProtect was 2103 prior to update and afterwards as well.
EDIT: I have no clue why, but the system feels smoother after this update. Interesting. Launchpad scrolling, scrolling and tab navigation within Safari have noticeable improvements for me.
Yeah. There is a new version 2103 now. It is at
http://swcdn.apple.com/content/down...d5832ivg90gh4xtns/XProtectPlistConfigData.pkg