Paint Shop Pro :: Automatically Save Copy Of Work In Progress Every X Minutes?

In older versions of PSP, auto-save would automatically save a copy of the work in progress every X minutes (depending on what was set by the user) and overwriting the previous version, including the original if not working on a copy of it.

In PSPX4, auto-preserve added the functionality of saving a copy of the original to avoid overwriting it, but it also has autosave setting.

Questions :

- what does the autosave do except save the image when changing from Edit to Manage to Adjust?

- does autosave automatically save a copy (even if overwriting) of the work in progress?

- if so, where do we set how frequently a save should be?