Ever heard the term “loose cannon”? Maybe this was simply a loose cannon which was allowed to fall overboard.
Also, just because a cannon was made in the 1580’s, doesn’t mean that it was not on a ship that was sailing 40 years later.
Also, just because a cannon was made in the 1580’s, doesn’t mean that it was not on a ship that was sailing 40 years later.
Are a hundred years later for that matter, they didn't change a whole lot during the period.