I finally got around to updating these after having let them gather dust for a while. These include bar charts showing the time periods that various releases were being worked on (QA = Quality Assurance) and were supported by the FreeBSD security team. The dates for 6.4, 7.1, and beyond are all “best-guess”.
I find the graphs much easier to understand than the text-format descriptions in various emails.
The data are up at schedule.html.