On April 8th, 2005, Ubuntu announced the release of version 5.04. This release was accompanied by a commitment to ongoing security updates for a period of 18 months, which has been reflected in the comprehensive set of Ubuntu Security Notices issued since that time. The support period for Ubuntu 5.04 is now nearing its end, and Ubuntu 5.04 will officially reach end-of-life on October 31st, 2006. At that time, Ubuntu Security Notices will no longer include information or updated packages for Ubuntu 5.04.

The supported upgrade path from Ubuntu 5.04 is via Ubuntu 5.10. Instructions and caveats for the upgrade may be found at
https://help.ubuntu.com/community/BreezyUpgradeNotes. Note that upgrades to version 6.06 and beyond are only supported in multiple steps, via an upgrade first to 5.10, then to 6.06. Both Ubuntu 5.10 and Ubuntu 6.06 LTS continue to be actively supported with security updates and select high-impact bug fixes. All announcements of official security updates for Ubuntu releases are sent to the ubuntu-security-announce mailing list, information about which may be found at https://lists.ubuntu.com/mailman/listinfo/ubuntu-security-announce.

The early Ubuntu releases changed the landscape of the Linux desktop. Quickly gaining popularity in homes, schools, businesses and governments around the world, Ubuntu is now widely considered the Linux desktop of choice. Ubuntu 6.06 LTS, released on June 1st, 2006, marked a new milestone for Ubuntu. Aimed at organisations with long-term and large-scale free software deployments, Ubuntu 6.06 LTS is a robust and reliable platform that will be actively supported with security updates and high-impact bug fixes for a period of 3 years on the desktop and 5 years on the server. Ubuntu 6.10 will be released in October 2006.