https://wccftech.com/first-windows-10-preview-build-of-the-year-is-out/

Microsoft is back to work and the Windows maker has just released Windows 10 Insider Preview Build 19541. As a reminder, before going for the holidays, Microsoft had started releasing these new builds from its development branch. However, the company had said that "while features in the active development branch may be slated for a future Windows 10 release, they are no longer matched to a specific Windows 10 release."

This essentially means that we don't know if these builds belong to 20H2 branch or a future version of the desktop operating system. Whatever the version these builds will eventually belong to, today's is the newest flight for Fast Ring Insiders bringing some new updates for them to test.