There is no commodore during peace time.
That’s a war time rank.
There is no more peace time.
Commodore is a position. A senior captain designated to act as flag officer in a temporarY capacity, like a cruise/deployment. I think in the late-70’s the rank Commodore,O-7 was briefly revived but quickly changed to Rear Admiral, Lower Half... the most god-awful and awkward sounding rank/title of all time.