Yes, that's the meaning it usually infers to me -- it's too late, no long possible, over and done.As English is not my mother tongue, is this meaning considered as a "colloquial expression" (from Idioms in the Free Dictionnary):
Some possibility or option is no longer available or likely.
In case it does, does anyone whose first language is English (or who practices it as if) have any idea what else the phrase used by the Cs might mean?
I know of no other meaning except the literal meaning -- a ship that has left the port or harbor. An unusual choice of words (ship, sail) and meaning (it's too late) to discuss a time machine maybe?