Samsung Galaxy S21 series is receiving the August 2021 Android security patch
Samsung released the August 2021 Android security patch for the Galaxy A52 a few days ago, followed by the A72 and A8 (2018). Now, the company has rolled out the latest security patch to three more smartphones - Galaxy S21, Galaxy S21+, and Galaxy S21 Ultra.
The new build carrying the August 2021 security patch comes with firmware version G99x0ZCU2AUGE, and the update for the S21 Ultra requires a download of about 300MB.
The update is currently seeding in China and should begin rolling in Hong Kong and Taiwan in a few days, with the rollout expected to expand to more countries in a couple of weeks.
If you live in China and haven't received the new firmware on your S21/S21+/S21 Ultra yet, you can try checking it manually by going to your device's Settings > Software update menu.