Am I at a disadvantage for uni applocations with bad gcses?

Long story short I wish to go to an oxbridge university but I feel that the gcse grades I was given in my past school were done unfairly (predicted grade thing) and had most of my grades reduced significantly but now it's too late to appeal. I have five 6s, two 7s , one 8, and one 4. I'm currently working at and aiming for a*a*a in my a-levels maths, physics, chem - if I achieve these grades what's the chances of me going oxbridge with these gcses?

The phrasing of the bold statement makes me laugh - it makes it sound as if there's more than Oxford and Cambridge. You certainly will be at a bit of a disadvantage with people applying to cambridge having usually a few 9/8s (since they class both as A*) but it will be Oxford that I would avoid with them using GCSEs more.

What course do you want to apply for?

Long story short I wish to go to an oxbridge university but I feel that the gcse grades I was given in my past school were done unfairly (predicted grade thing) and had most of my grades reduced significantly but now it's too late to appeal. I have five 6s, two 7s , one 8, and one 4. I'm currently working at and aiming for a*a*a in my a-levels maths, physics, chem - if I achieve these grades what's the chances of me going oxbridge with these gcses?

Have a read of “Are these GCSE’s good enough for…” as it covers Oxbridge.