Epic Cards Battle

I realized that enhancing cards would increase the cap of a card (e.g. 30lv silver card, cap3>4). However, I wonder if the cap will further increase or not if I continue enhancing the 30lv card. If yes, at which level will its cap increase? THANK YOU=)

correct me if im wrong, but i think card cap is raised 2x
(and i would be glad as well to know any feedback regarding this)

Once when a card reaches level 20, and another time somewhere between lvl 31 and lvl 35