*snip*
Let's say, for this example, you have somewhere in your ranks Commodore, Rear Adm, Vice Adm, in that order with no other ranks between.
Now lets say you aren't manually assigning minimum ranks to naval admin commands and aren't marking officers as "do not promote."
In this situation, for an admin post to
require a Vice Adm, it has to have a direct subordanant post that requires a Rear Adm (whether that is another naval admin, or a post on a ship). If that Vice Adm admin post is open, a Rear Adm who is currently filling a Rear Adm post will get promoted. If there are no Rear Adms anywhere at all, then there is de facto at least one open Rear Adm post for a Commodore to get promoted into, who will then get promoted for the Vice Adm post on the next construction cycle.
For the kind of gaps you're talking about, you would have had to accidentally or intentionally manually set your naval admins to include such a gap, or have had to mark all existing officers of a given rank (such as all your Rear Adms in the example above) as "do not promote." In other words, it is literally a problem you have to micromanage yourself into.
The key thing to remember is that officers don't have to only be promoted to their direct superior's job. In your second post about this, you're describing a Vice Adm in a naval admin post who is directly superior to other naval admins who are either rear upper or rear lower. In this case, a rear upper would get the promotion if that vice post is open (but not necessarilly one of the rear uppers that was in that part of the hierarchy), which would open a rear upper post for a rear lower (likewise, from anywhere in the hierarchy) and so on.
