https://adtmag.com/articles/2020/02/19/android-11-preview.aspx

Google announced an early developer-only preview of Android 11, inviting coders to put the next edition of its flagship mobile OS through its paces on Pixel 2, 3, 3a, or 4 devices.

The developer preview follows the September 2019 release of Android 10, the source code for which was donated to the Android Open Source Project (AOSP).