Assignable buttons question

Hi all,
On my Audya 4 there are sixteen assignable buttons just below the display.
I am wondering, does anyone know if it is possible to assign any of the four style variations to any of these buttons?
From what I have found out so far, it doesn't seem to be possible, only the fills?
Many thanks for any help!

Hi Christian,

on my Audya 5 I can assign the style variations to the buttons.

They are listed as "Arr A" to "Arr D".

From "Fill 1" 4 steps back is "Arr D", prior that "Arr C" and so on.

Hi,
Many thanks for your reply.
OK, so for example, if I want to program the assignable button 3 as variation c, how do I do that?
Many thanks!