Microsoft is gearing up to release Windows 10 version 21H1, aka the Spring Update, as they broadly release the feature update to all Windows Insiders in the Beta channel. Microsoft is more aggressively testing the new feature update with a much larger audience and a greater diversity of hardware to resolve bugs and conflicts before the new version is released to the public. Microsoft has already started pushing down the necessary files to current public versions of Windows 10. Windows 10 Sun Valley feature update is expected for release in the fall of 2021.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-21h1-inches-closer-to-release-heres-the-latest-news/