Any way to make Callsign say a word?

I know that title seemed kinda off. But anyways…

I realized that @MishaCamp has the Callsign “Superman”, and the ATC says the actual name for him instead of saying “Sierra uniform blah blah”, you get the point. Is that only for staff or?.. Because I just want my Callsign to be FlyFy without ATC doing the entire phonetic alphabet.

Changed with the last update. I just haven’t updated mine since then.