Microsoft chooses Build 19043.928 as the final release for Windows 10 21H1 Update. It should start rolling out to all users in May 2021.
Microsoft has designated version 19043.928 as the "final" version of Windows 10 update 21H1. On April 28, in a Windows Insider blog post, this build was named the "May 2021 Update" and made available to all Release Preview channel participants for download.
Windows 10 21H1 will be a minor update for Windows 10 20H2, which was a minor update for Windows 10 2004. Microsoft may begin the official rollout of 21H1 on May 11, the date of Patch Tuesday.
Microsoft indicates that the "Insiders" of the Beta and Release Preview channels are already on the "new" builds 21H1 since the start of the week, with the release of build 19043.964. In the Release Preview channel, it is possible to get the 21H1 / May 2021 update by proactively checking for it, going to Settings> Update & Security> Windows Update.
Microsoft has made update 21H1 available for commercial validation through the Windows Insider for Business program starting in March. These attendees have been able to test Windows 10 Enterprise and Pro editions of 21H1 since then.