Gateway is possible but look on the websites of the Unis you want. Gateway is not just on grades but contextual offers as well. I just asked the head this morning if redoing Year 13 is allowed and he said rarely allowed. You can study alone at home for a year if you want to resit A Levels or maybe try another college. RVC Gateway is heavily biology based - my biology is very good so I think I would be bored on it. Gateway costs the same as any uni course so unless your rich try and avoid it as will still cost £9250 uni fees, accommodation and other expenses easily £20,000 + interest to be repaid.