VVL solves RON requirements

Hi, I have this problem which I dont understand.
This engine has cam profile set to 20 and cannot run properly on 95 RON fuel.
This is the same engine with same cam profile but I used VVL with second cam profile of 100, the engine can now run on worse fuel in the entire rev range.
I think that the fuel requirements should stay even when second cam profile is used. If I´m missing something important just point it out I wont be mad.
This engine has cam profile set to 20 and cannot run properly on 95 RON fuel.
This is the same engine with same cam profile but I used VVL with second cam profile of 100, the engine can now run on worse fuel in the entire rev range.
I think that the fuel requirements should stay even when second cam profile is used. If I´m missing something important just point it out I wont be mad.