On November 7, Microsoft rolled out KB4529943 for devices running Windows 10 1903 May 2019 Update. This is a UUP update available for the users participating in a testing program. KB4529943 will be available to Windows 10 devices that are not involved in the Unified Update Platform Insider Program after a little time. Microsoft shared its plans to migrate from a standard update deployment system in Windows 10 to “UUP” in Nov 2016. The main benefits of the program are reducing the size of updates and the time it takes to deliver and deploy. The Redmondians claim that the new method can minimize the size of updates by about 35%. The feature uses differential update packages and devices receive only the changed code, and not all packages again.
Differential boot packages contain only the changes that have been implemented since the previous device update, and not the full assembly. After implementing UUP, when switching from one major update to another, users will notice a decrease in the size of downloaded files by about 35 percent.
KB4529943 UUP Update for Windows 10 version 1903
This package is available to a confined group of users who participate in the UUP Insider Program. KB4529943 is in a test phase so it can only be installed on user’s devices who joined the UUP test program.
The reduction of the size should be a useful improvement for most users and organizations that use Windows 10 1903. As a result, the updates will be delivered faster, and many users will notice faster installation.
You can receive KB4529943 from Settings => Update & Security => Windows Update => Check for updates.
You can download the UUP update from Windows 10 right now to manually install it from the Microsoft update catalog.
Source – Knowledgebase.