My high school had a /34 running RSTS/E, with roughly a dozen terminals on-campus, mostly in the lab. Even in 1980, I recall my teacher warning about Y2K, though not yet named as such. Fast forward 20+ years, and I would set up SIMH, install RSTS/E on it, and discover that version 7.0, which was what I used at the time, was not Y2K-compatible.