Sony has started updating the Xperia 10 and Xperia 10 Plus with Android 10 in some regions. The software is bundled with the March 2020 security patch along with all the standard Android 10 features. It will make its way to eligible devices OTA in the coming weeks.
https://www.notebookcheck.net/Android-10-has-arrived-for-the-Sony-Xperia-10-and-Xperia-10-Plus.464371.0.html