I don't think git or subversion existed back then
According to Wikipedia, SCCS was developed in 1972 and RCS in 1982. However, in those days most of us could not afford a Unix machine. It was only end 1992 when I built a system running Linux and all of this became much easier. I became coordinator in 1996, and my predecessor PA0GRI had used Unix at home much earlier than me. (I think he had a Unix system on packet radio in 1988 or so) He developed the scripts used to send update mails to the robot, which I continue to use. These just save a copy of the mails sent to the robot. That is about 5MB now. Does not seem much, but there have been times this was most of the harddisk capacity of a computer... :-)
Rob