During the week leading up to the final release, the images produced are all considered release candidates. In an ideal world, the first one would end up being the final release, however we don't live in an ideal world, and this week is used to shake out the last release critical bugs and get as much testing in as possible. From here untilFinalRelease, changes are only permitted at the release team's discretion, and will only be allowed for very high-priority bugs that might justify delaying the release.

SeeFreezeExceptionProcess.