Samsung is apparently testing out an Android 11 update for the Galaxy S10+. An S10+ running on the new operating system was recently spotted on Geekbench. While Android 11 won't even be released until May 2020, this indicates that Samsung's making a strong push to get the OS on the Galaxy S10 series as early as possible.
https://www.notebookcheck.net/Samsung-Galaxy-S10-running-Android-11-spotted-on-Geekbench-OneUI-3-0-could-be-in-the-works.454697.0.html