Realme started rolling out October 2021 OTA update for Realme X devices. The Rollout is phased and it will reach your phones soon.
Realme X was released in July,2019 with Android 9.0 out of the box.
Recently, last month Realme X received Android 11 with Realme 2.0 UI a stable release, and users are still getting major Android 11 update yet with slightly modified F.04 build. As multiple users reported that they were having issues after upgrading from Android 10.
So Realme rolling out a stability fix to improve the system performance of the device, still yet to get the latest security patch update yet this update is like Hotfix for the device.

Source>>Realme Community
| Android OS | Update | Release Date/Status | Estimated Months |
| Android 9 Pie | Out-of-the-box | September 2019 | Nil |
| Android 10 | First OS update | March 2020 | 6 months |
| Android 11 | Second/Last OS update | September 2021 | 11 months |
The Realme X has received two major OS updates with Android 10 and 11. Therefore, the chances of a third major OS update with Android 12 are unlikely.
Hence, the Realme X Android 11 Update was the last major OS update on this device.
However, it will continue to receive Security updates this year at least.
The Realme X had received its Android 11 update recently and now has received October 2021 Update.
Once the update is available on your device, you can head over to Settings >> About Phone >> Software Update section to update your Realme device with the latest security/software update.
For more Realme Android updates please download our Android App – Available on the Play Store