The kernel has a release cycle of every one or two weeks (rc-release) depending on the changes and quality of new code that Linus Torvalds gets. Interesting enough, Firefox is adapting to that method of release scheduling as well. Obviously there is no such thing as a time-scheduled release. There are just incremental upgrades and new features. New features obviously always have to go through several incremental stages.
Incremental upgrades
Published
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