OnePlus has announced that its plans to scrap OxygenOS, the OS it has used since 2015. A 'Unified and Upgraded Global Operating System' will arrive in its place, which also replaces Oppo's ColorOS. There will be no OnePlus 9T or OnePlus 9T Pro this year, either.
https://www.notebookcheck.net/OnePlus-scales-back-flagship-smartphone-production-as-it-announces-the-end-of-OxygenOS.562726.0.html