Windows is shipping new updates early this month. In the latest "Windows 10 Fall Creators Edition Update" version, they now have a pretty panel and call them "Feature Updates" rather than bug fixes, but you know what that means.
Info on the Windows Security Site [1] seems to indicate it's a fix for many of their security products. That, combined with the week-early date, make me suspect something's in the wild they don't want people to catch.
Word to the wise.
"Working on updates 0% Don't turn off your machine. This will take a while" my machine tells me. Still. After a while.
Where do you want to go today?
[1] https://portal.msrc.microsoft.com/en-us/security-guidance