I suspect that it may not recognize versions that you saved yourself. Pages is probably keeping its own backups after you select the option.
Thanks. I'll keep an eye out and see what happens with normal open/edit/close actions. When I said checking the "Backup previous version when saving" didn't help, I only meant it didn't allow me to seek a backup from "Revert to Saved" under File.
It did make backups when I saved after changes, but they were all separate documents in the saved folder - not quite Time Machine-like behaviour. I have a habit of saving constantly, so the saved folder could get a bit bulky.
