Oneplus announced the release of OxygenOS 11.1.1.1 based on Android 11 with a September 2021 security patch via OTA for Oneplus 6. Initially, The OTA will be received by few users of Oneplus 6 randomly. After making sure that there are no critical bugs, then the rest of the Oneplus 6 users started getting the update.
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The Oneplus 6 is released in the year 2018, May 17 with Android 8.1(Oreo) operating system(OS).

Source: Oneplus Community
| Android OS | Update | Release date/status | Estimated time |
| Android 8.1 Oreo | Out-of-the-box | May 2018 | Nil |
| Android 9 Pie | First update | September 2018 | 1 month |
| Android 10 | Second update | December 2019 | 3 months |
| Android 11 | Last update | August 2021 | 11 months |
This device has received three major OS update, and its highly unlikely it will get Android 12 update, Only few security updates and it will end of updates for this device.
once the update is available on your device, then you can head over to Settings >> About Phone >> Software Update section to update your OnePlus with the latest September 2021 security patch update with OxygenOS 11.
Firstly the update is only available for few users of Oneplus 6 after ensuring that there are no critical bugs remaining users will get the update.
Note: Backing up data is essential, as the update may encounter bugs and there might be a chance of data loss.
For more OnePlus Android updates please download our android app – available on the Play Store