Change deadlines happen two weeks before the public release of each Fedora Alpha, Beta, and Final release.
At the change deadline, pushes to the branched development tree are suspended until the release candidate is accepted.
A push is a a release engineering term for moving a package into a particular tree or repo of packages. After a release has been branched, a new or updated package must receive testing feedback via Bodhi before it is allowed into the stable branch.
The stable branch is the release tree or yum repo of packages that were originally branched from rawhide or have been updated through the Bodhi process. For example, in Fedora 14 the name of the branched tree is pub/fedora/linux/development/14.
See picture at fixme
Alpha & Beta Public Releases
At the change deadlines for Alpha and Beta, pushes to the branched development tree, for example ../development/14, are suspended until the Release Candidate has been successfully tested and is being staged to the mirrors.
Only blocker bugs of a public release (critical path or not) can be pushed to a stable branch during this interim period.
Pushes may continue to the updates-testing tree
Final Release
After the change deadlines for the Final release no more updates are made to the branched development tree, for example ../development/14.. The only exceptions are accepted blocker bugs.
All updates afte this time are considered zero day updates of the releae and pushed to the updates repo which is available on the public availability date. For example, for Fedora 14 this repo is ../pub/fedora/linux/updates/14