Samsung is already running a public beta program for the One UI 3 update based on Android 11 for its flagship Galaxy S20 and Galaxy Note20 series. While the company has not revealed any release timeframe for the final update, it looks like it is planning a late November or early December release for the update.
The company has updated the Malaysian landing page for One UI 3 (via Droid Life) and it says "One UI 3 will be available from Nov. 2020 or later." The South Korean page of One UI 3 also says that the update will be released after November 2020. The U.S. page for One UI 3 does not mention anything about its release date. Nonetheless, it looks like Samsung is planning on rolling out the One UI 3 update for the Galaxy S20 and Galaxy Note20 series in at least selected markets by the end of November.
The company has been frequently rolling out updates for the public beta build of One UI 3 for the Galaxy S20 and Note20 series to squash all the bugs being reported by testers and to fix stability issues.
One UI 3 is based on Android 11 and comes with a number of new features and enhancements. This includes a streamlined Settings menu, more customization options for the Always-on Display, revamped system apps and notification shade, smarter Bixby Routines, and more. You can read about all the new One UI 3 features here.