Are you thinking of an equivalent to calibre's checkpoint feature?
Anyway, Sigil doesn't do a lot of history saving. AFAIK, the only history anywhere is the internal undo/redo of the text editing widgets themselves (which will be trampled by plugins, I think).
Audit trails are at least currently the biggest distinguishing factor between Sigil and calibre.
...
There are
no command line switches, although you can at least pass the name of the file it should open with.
