Abiword releases a new version that adds compatibility with WordStar 4.0 documents. It also completely updates the user interface to use pie menus. This would be a feature enhancement with a major user experience change, and would not be allowed.
Additionally, multiple kernels can be installed/booted, allowing users to boot older kernels in the event newer ones fail to work, and allowing time for kernel maintainers to fix any critical bugs in new kernels on older stable releases.
After branching, there are three freezes, <<post-branch-freeze>>, <<beta-freeze>>, and <<final-freeze>>.
A link:https://fedoraproject.org/wiki/Releases/Branched[Branched] release exists for part of the development cycle. It starts as a fork of Rawhide and eventually becomes the next stable release. All successfull branched composes should meet the link:https://fedoraproject.org/wiki/Basic_Release_Criteria[Basic Release Critera].
All updates go to link:https://fedoraproject.org/wiki/Repositories#updates-testing[_updates-testing_].
All updates pulled into the release MUST fix an accepted blocker or freeze exception bug.
All updates still go to link:https://fedoraproject.org/wiki/Repositories#updates-testing[_updates-testing_].
AOL changes their instant messenger protocol in a way that requires an update to libpurple. The only upstream version of libpurple that supports the new protocol is an ABI break relative to the version in the current Fedora release. Rebasing would be allowed since this is an interoperability requirement.
As soon as a build is completed, a Bodhi update is automatically created. The update is used to gather test results. If the gating tests pass, the update is marked stable after a few minutes, pushed stable, and will be added to the next nightly compose.
At this point, the Bodhi update system is changed for the branched release to behave as it does for stable releases (see below) instead of Rawhide. From this point onward maintainers must create updates before packages become available to users and updates pass through link:https://fedoraproject.org/wiki/QA:Updates_Testing[_updates-testing_] to allow for feedback. Updates are moved from link:https://fedoraproject.org/wiki/Repositories#updates-testing[_updates-testing_] repository to link:https://fedoraproject.org/wiki/Repositories#fedora[_fedora_] repository after appropriate karma requirements have been reached. Bodhi sets reasonable defaults for karma and enforces minimum requirements for updates. <<karma-requirements>> for updates are described below.
automake releases a new version that changes some warning conditions to errors. This would break the build process for existing packages, and would not be allowed.
Avoid ABI/API changes where possible. If unavoidable, use a side-tag to rebuild packages.
Avoid any change that breaks composes of Live media, install media or testing.
Avoid changing the user or developer experience if at all possible
Avoid Major version updates, AI breakage, or API changes if at all possible
Before Updates-testing Activation
Beta Freeze
Beta to Final Freeze
Branched release
Branched releases use the update feedback system (link:https://bodhi.fedoraproject.org[Bodhi]): at first just like Rawhide (updates are automatically created when a build finishes, tests run and builds are automatically pushed into the next compose), but then after <<updates-testing-activation>> they switch to using it as stable releases do (maintainers must create updates and submit them for testing, etc).