The Notifications add-on (free and premium) is solely based on a user gaining or losing points. Basically the add-on hooks into myCRED and waits around for a user to gain or lose points. When this happens, a “snapshot” is taken and saved.
When a user then visits your site, one of the first things that happen before the page loads is that myCRED will check if there are any new “snapshots” for this particular user. If there are, these then called in your pages footer (to allow everything else to load first).
In the footer, a script will then run and convert these “snapshots” into a message you actually see with the css styling and position applied.
So you see there is nothing here that will also detect a rank promotion or detection. Instead the users sees the point gain / lose that got him to the new rank. But there is one exception.
If you have a custom hook that awards points for rank promotions / demotions, meaning that when a user changes rank you give them extra points, you might use the Log template as a message saying something like “Bonus Points for Rank Promotion” which is one way to show a “notice” when a user changes rank.
But you know you can add in more. The script that handles the “snapshots” can be customized and you could add your own “snapshot” which just states e.g. “Congrats on reaching a new rank!”.
I am thinking I think i will add something in for the premium add-on to show a custom notice when you rank up / down. I think others might like it as well.