Linux 5.15 Is This Year's LTS Kernel
Well, Greg Kroah-Hartman has decided on Linux 5.15 being the LTS kernel for 2021. The Kernel.org release page has been updated to reflect the newly-released Linux 5.15 kernel being an LTS branch.
At the moment the LTS period projects Linux 5.15 LTS to be end-of-life in October 2023. However, as is usually the case, this can be extended by years given enough industry support. If enough users/developers and organizations step up for committing to testing the new point releases and actually using the LTS kernel in production, the LTS period can be extended by several years.
Last year's Linux 5.10 LTS kernel is currently planned to be maintained through end of 2026 while 2019's Linux 5.4 LTS through end of 2025. So it's quite possible Linux 5.15 LTS could be maintained through end of 2027 if those conditions are met.
Linux 5.15 is quite an exciting update while some big additions are also en route for Linux 5.16 that led some to hope Linux 5.16 would be the LTS, albeit it's a never-ending game with upstream kernel development.