Are you taking about AS grades or Predicted grades?
If they are predicted grades for A2, then you might not be looked at. I don't know about the 6 year course, but I applied for the 5 year course and the AAA is basically their minimum, and if you don't have the predictions for it, I was told you just get rejected. This would be ABB in your case for the 6 year course.
I think it might be the same situation as they are both so competitive, they normally see if you meet the minimum, and if you don't you just get eliminated and looked at no further.