The developers of Linux Mint project decided to use as the basis for future releases of the distribution only releases of Ubuntu with a long term support (LTS) with periodic back ported new versions of programs. Future release of Linux Mint 17 will be maintained until 2019 and the following two years will be the basis for interim releases 17.x, which will include new versions of critical applications, including new releases desktop Cinnamon.
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Building distribution only on the basis of the LTS version of Ubuntu will ensure a constant level of stability of the distribution, will facilitate support batch base, would allow time for the development of original components of Linux Mint, such as Cinnamon, and eliminate problems when users upgrade to the next minor version.
Thus, the scheme future releases is as follows: In the near future will be released Linux Mint 17.0 (already published release candidate), based on Ubuntu 14.04 LTS. Prior to the release of Ubuntu 16.04 LTS once in six months will be an interim version of Linux Mint 17.1, 17.2, 17.3, for which you will be back porting of new versions of programs. After the release of Ubuntu 16.04 LTS in 2016 will be presented to the release of Linux Mint 18.0 to be switched on work backporting and branch Linux Mint 17.x going to be put into maintenance mode allowing only the release of updates to address vulnerabilities and serious problems.