Samba3 Release Planning
From SambaWiki
The regular Samba3 release cycle intends a new major release every six month (around July 1 and December 15). Each major release turns into maintenance mode when the next major release is out. Maintenance mode means that only severe bugs and security issues will be fixed.
After six month maintenance mode, the series will be discontinued.
Example: If 3.4 is the current release series, 3.3 is in maintenance mode and the maintenance of 3.2 has been stopped (approximately) with the release date of 3.4.0.