That all makes sense, but what I was saying is that it doesn't make sense to me that he got promoted to the rank of Captain and then got bumped back down to Commander. I'm not talking about the position of Captain, just the rank.
Even if he was "reduced " back to first officer, there is no reason he couldn't have retained the rank of Captain..
Both the Captain and the Executive Officer of the current USS Enterprise (CVN-65) are Captains by rank. Captain William Hamilton and Captain Gregory Huffman.