Ubuntu 13.04 RARING RINGTAIL Release Schedule

Ubuntu being an open source initiative is bound to be a constantly changing environment. There have been around 16 releases of Ubuntu so far and the 17th is all set to roll out in April of 2013.
All its Beta release have ensured the fixing of majority of the bugs arising during user testing. We expect the final version to be released soon to incorporate a new look and feel in the Ubuntu Lineup.

The new version will be available around April of 2013. But the Beta version will all be available before the release of the final version in March.
For Ubuntu 13.04, the developers decided to return to a normal development cycle and modified the release schedule to two Alpha versions, one Beta release and one Release Candidate.

The schedule of the release of Ubuntu 13.04 Raring Ringtail with exact date is as follows:

• March 28th, 2013 - Beta release
• April 25th, 2013 - Final release of Ubuntu 13.04

Ubuntu 13.04 Raring Ringtail Release Schedule Wiki.

source : http://www.noobslab.com/2012/10/ubuntu-1304-release-schedule.html