From Second Life Wiki
Server Release Candidates
When a new version of server is ready for the main grid it needs to prove itself in a release candidate channel for one week first. This is what we used to call a pilot roll. Once a 'Server Release Candidate' has proven itself it will be rolled out to the entire main grid. We might have as many as three 'Server Release Candidate' channels on the main grid at the same time.
Server RC Channels
Server Beta Office Hours
We meet once a week to discuss upcoming changes to server and how you can get involved. We meet Thursdays at 3pm in the Morris region on ADITI. There are more details here: