Oneplus 9RT already received OxygenOS 12.1 Beta update. But before giving OxgenOS 12.1 stable update Which is 1 month away , Oneplus has given final OxygenOS 11.3 build for 9RT.
OxygenOS 11.3 A.10 Changelog
• Optimized network stability
• Improved system stability
• Updated Android security patch to 2022.06
• Fixed the occasional issue that camera crashed abnormally