FreeBSD 5.3-RC1 just appeared on the FreeBSD FTP servers. If only one Release Candidate is built (as planned), then we might see 5.3 RELEASE in about a week. I imagine 5.2 RELEASE will appear the first week of November, as the release engineers have high standards for this version. 6.0 will be CURRENT although it has been treated as such for a few months now. With 5.0 the STABLE tag will migrate from the 4.x line to the 5.x.”]
Source: https://taosecurity.blogspot.com/2004/10/freebsd-5_18.html