Don't mean to nitpick too much, as there may be a rank system that I am unfamiliar with. (One specific to semi-medieval anthropomorphic foxes,
for example).
In the US navy, a Commander would be an O-5, and a Captain, an O-6. In the Marines, as in Army/AF, a Captain would be an O-3, then you would go Major, Lt Col, Col, various Generals.
Unless he's talking about a demotion?
(Crazy naval ranks anyway ...)