Microsoft has set Windows 10 21H1 (May 2021 Update) for broad rollout, making them available to everyone via Windows Update.
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Windows 10 21H1 will be offered to all devices that are not set to defer feature updates or are not affected by compatibility blocks.
“Windows 10 21H1 are designed for broad deployment”, says the company in a status update of the Windows Health dashboard.
“As always, we recommend updating your devices to the latest version of Windows 10 as soon as possible to ensure you can take advantage of the latest features and advanced protections against the latest security threats.”
Microsoft officially began the rollout of Windows 10 21H1 in May 2020, but so far it has not been offered to everyone who checks for updates via Windows Update.
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This is due to the fact that Windows feature updates enter targeted rollout immediately after release to test build quality on targeted machines, including those with modern chipsets.
After Microsoft determines that a version is ready for rollout on most Windows 10 devices, it moves it to “wide rollout”, the next rollout phase.

Windows 10 21H1 is being released as an activation package for Windows 10 2004 and Windows 10 20H2, allowing systems running these versions of Windows to update very quickly and with a single restart, just as they would install a monthly update.
Given that all features of 21H1 are included in Windows 10 2004/20H2, the activation package will act as “master switch”, enabling the dormant capabilities of the operating system.
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On devices with older versions of Windows 10, you will need to install the full update, which will take longer.
You can also use the Windows 10 Media Creation tool to upgrade or create an ISO for “clean install” of Windows 10 21H1.
Additional information about installing the May 2021 Update on your system is available at this link.
Source: bleeepingcomputer.com
