Skipping ranks, even? LOL what? To be fair it hasn't happened, but with next ep being the final ep, chances are we'll find out he accepted the position.

Julio getting promoted would be the equivalent of Stabler from SVU getting promoted: not gonna happen. Too many incidents on his record of being a hot head with perps to make that happen, even if he's put some distance (as in years) between them. Typically brass has a long memory in this regard, and would not want to reward nor put in a supervisory position (as he'd be the lieutenant of criminal intelligence if he accepts) someone with a history of flying off at the handle.

However...this is a fictional, and next episode is the final episode (unless we get some sort of miracle between now and January 9th), so this is Julio's happy ending.