Microsoft released KB5005611 for Windows 10 in versions 21H1, 20H2 and 2004. This update is available through Windows Update and WSUS for Business, but the company has also released offline installers.
KB5005611 is an optional update, so no download or installation will take place unless you manually select the update and click "Download and Install". It does not include security fixes, but it does bring a lot of improvements and bug fixes.
KB5005611 uploads the build numbers in version 21H1 - Build 19043.1266, in version 20H2 19042.1266, and build 19041.1202 for those devices that are still running the 2004 version.
Remember that support for Windows 10 version 2004 expires in December, and Microsoft will soon stop offering optional updates.
On your devices, the update will appear as:
2021-09 Cumulative Update Preview for Windows 10 Version 21H1 for x64-based Systems (KB5005611)
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2021-09 Cumulative Update Preview for Windows 10 Version 20H2 for x64-based Systems (KB5005611)
You can install the update via Windows Update as mentioned above, or download the offline installer you are interested in from the link below
Windows 10 KB5005611: 64-bit and 32-bit (x86).
Using the link above, you can find the installers in the Microsoft Update Catalog. These standalone installation files (.msu) allow you to install the update offline and can be used on any device.
However, make sure that you have downloaded the .msu file that is compatible with your system version, and the Windows 10 processor. You can view this information from the Settings - System - Information path.
More information on the update from official webpage.