Google just released the Android 11 Developer Preview! You can download it on your Pixel 2, Pixel 3, Pixel 3a, or Pixel 4.
The Android 11 Developer Preview beta will be available at some point “in the next several weeks.” This is the first build, so that mostly makes sense. It’s probably not stable enough for everyone to run yet.
UPDATE: What’s new in Android 11?
If you’d like to get on Android 11, you have two choices: factory images or OTA files.
Android 11 DP1 build info:
Date: February 19, 2020
Emulator support: x86 (32/64-bit)
Security patch level: March 2020
Google Play services: 20.04.14