Yeah Casio did something funny there.  A good example is the Big Band style number 70.  You can tell there is more than (2) fill ins with this style.  
Here's how.  When you play variation 1 and press that button again to activate the variation one fill in.., you get just that.  However if you press the (fill-in next) button that takes you to variation two, you get a different fill in than assigned to variation one.  
Then while variation two is playing you press the variation two button to activate that fill and you get yet a different fill in.  However if you press the (fill-in next) button to go back to variation one you get yet another fill.
I counted them and there (4) fill ins for this style.  I know this because this was one of my favorite styles on the MZ-2000.  I thought I was hearing things when I realized that ALL four fills were carried over on this style.  I haven't really checked all the styles.   Maybe I'll tackle that tonight.  I think it's also on a few others.
Squeak
_________________________
GEAR:  Yamaha MOXF-6, Casio MZX-500, Roland Juno-Di, M-Audio Venom, Roland RS-70, Yamaha PSR S700, M-Audio Axiom Pro-61 (Midi Controller).  SOFTWARE:  Mixcraft-7, PowerTracks Pro Audio 2013, Beat Thang Virtual, Dimension Le.