New cumulative updates are rolling out for supported versions of Windows 10, including the October 2018 Update, the April 2018 Update and the Fall Creators Update. Microsoft has also released a cumulative update for devices running the Insider preview builds of the upcoming Windows 10 May 2019 Update. All the changes are aimed at enterprises and there’s nothing in the basket for consumers. There may be issues using the Preboot Execution Environment (PXE) to start a device from a Windows Deployment Services (WDS) server configured to use Variable Window Extension.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-april-2019-cumulative-updates-released-with-fixes/