Throughout the story, I found a quest that unlocked Medic Gunner's ability to go beyond rank 10. However, there is no marking in the UI for classes that can go above rank 10. There is an obnoxious warning when you have a class that's currently maxed out, telling you to go play something else, but that doesn't seem to show up on any of my rank 10 classes that I unlocked - only the base 6 classes.
Now, I would expect this message to be an indicator, even if a poor one, but I don't seem to get CP on classes that it doesn't warn me about either. So currently I have no idea if there's a simple indicator that tells me what classes can go to rank 20. Is there one?