Oneplus officially announced the release of OxygenOS 11.0.11.11 (NA & EU) and 11.0.10.10 (IN) with the October 2021 security patch for Oneplus 8T.
The Oneplus 8T was updated with OxygenOS 11.0.10.10 along with the august 2021 security patch in NA and EU regions, now the update is released in India along with October 2021 security patch.
It's surprising to see Oneplus also bundle Apps with OTA updates, just like other OEMs who are bundling bloatware Apps through updates, But Oneplus this time only bundled Google Specific App, which may not be bloatware but a sign they might bring other apps if needed.
The OnePlus 8T was released in October 2020 with an Android 11 out-of-the-box.

Source>> Oneplus community
The OnePlus 8T has an Android 11 OS out-of-the-box. Therefore, it is eligible for three major OS updates.
The OnePlus 8T will receive three years of major OS updates and four years of Security updates.
Android 14 will probably be the last major OS update on the device, And Android 12 will be its first major OS update.
Check your device>>> OnePlus Android 12 update list
The OnePlus 8T Software Update with OxygenOS 11.0.11.11 is currently rolling out in Europe and North America. But, it is soon expected to expand to other regions soon.
Once the update is available on your device, you can head over to Settings >> About Phone >> Software Update section to update your OnePlus device with the latest update.
For more Oneplus Android updates please download our Android App – Available on the Play Store