https://wccftech.com/windows-10-kb5005611-for-v21h2-and-v21h1-is-also-out/

After making Windows 11 available for eligible devices in the Release Preview Channel, the Windows maker has now released Windows 10 builds for the Insiders in the Channel, as well. Windows 10 Build 19044.1263 (for upcoming version 21H2) and Build 19043.1263 (for the latest version 21H1) are both available for Release Preview Channel Insiders.

If you are already running Windows 10 version 21H2, this update (KB5005611) will be offered to you automatically. Or, you can seek the upgrade to version 21H2 via Settings > Update & Security > Windows Update. However, this will only work for you if you were moved from the Beta Channel to the Release Preview Channel because your PC did not meet the hardware requirements for Windows 11.