Microsoft will end it soon support for Windows 1909 version 10, also known as “19H2” or November 2019 Update. So the Redmond company started urging users of the older version to upgrade directly to the 2004 version.
After May 11, 2021, the Home, Pro, Pro Education, Pro for Workstations versions of Windows 10 version 1909 and all versions of Windows Server version 1909 will no longer receive security updates.
Microsoft has already started upgrading devices with Windows 10 in version 1909 to Windows 10 of version 2004. With the upgrade to version 2004, you should not encounter any problems, as according to the company this version is considered reliable.
Interestingly, the latest version of Windows 10 is now version 20H2. In fact, all of its features are also available in the 2004 version with cumulative upgrades. The "upgrade" installs an activation package that activates only a few new features. It was also used for Windows 10 of 1903 and 1909, and now for 2004 and 20H2. However, the 20H2 is not yet available to 1909 users.
More information can be found from here.