https://wccftech.com/samsung-officially-rolls-out-android-12-beta-in-the-u-s-for-galaxy-s21-series/

Although the stable version of Android 12 is still not out from Google, that does not mean that other companies will sit and wait. Samsung has decided that it will start releasing the Android 12/One UI 4.0 beta in the U.S. starting today, and by now, many users who enrolled in the program have started receiving the update. The update is currently only limited to the Galaxy S21 series of devices, but we will get more devices added to the beta program.

With that said, Samsung has also confirmed several other markets where we will see the update. The Android 12/One UI 4.0 beta will be available in the UK, China, India, Germany, Poland, and South Korea.