Microsoft Update の日

2019-05 x64 ベース システム用 Windows 10 Version 1809 の累積更新プログラム (KB4497934)
May 21, 2019—KB4497934 (OS Build OS 17763.529)

Starting with update KB4497934, we are introducing functionality that allows you to decide when to install a feature update. You control when you get a feature update while simultaneously keeping your devices up to date. Feature updates that are available for eligible devices will appear in a separate module on the Windows Update page (Settings > Update & Security > Windows Update). If you would like to get an available update right away, select Download and install now. To find out more about this feature, please go to this blog.

How to get the Windows 10 May 2019 Update
Windows Update で「更新プログラムのチェック」して May U が表示されたら「Download and install now」を選択しろとな