Few questions on Character card deck system

I know they technically have a "4th job", but they also technically don't, because their "4th job" is "Completion of X".
Like I said, Max said Cygnus only go to Rank A and no one's been able to confirm or deny it yet, so I'm sticking by it that Cygnus can only go up to Rank A due to lack of "Official 4th job".

But they technically do.

If you do the end Cygnus quests, you get a 4th Job tab, it just has no skills in it.

I wonder if you just need to do those quests for it to count as an S Card.

-points at green Cygnus card- Level 120 with Rank A. I have completed the 'fourth job advancement' quests on it