How will taking 5 IGCSEs affect me in applying to UK universities if I score 8–9 on all subjects? will getting A-A* on 4 A-Levels help get into Oxbridge/Imperial?

I am a British citizen who took the IGCSEs abroad. I changed my school after the first year of the course. This is why I took 5 subjects as many of the courses offered were different. I am hoping on getting into Oxbridge or Imperial London. Will the fact that I took 5 subjects create a large barrier for me? Or will scoring 8–9 on all of them give me the same advantage as those who took more (and scored lower on some)? Are the IGCSEs even important when applying for universities if I were to take 4 A-Levels and managed to score A-A* on all? And would it be helpful to mention the shift in schools/courses in my application? Also, I skipped an abroad grade which now puts me ahead of UK students. This gives me the opportunity to stay in the UK this year and repeat the GCSEs, allowing me to take on more subjects. However, I will have one year to cover the 2 year program. I also thought about studying AS-Level abroad, and then return to the UK to do my A-Levels. In this case I will know the first year ahead, allowing me to focus more on studying for my A-Levels, helping me get A-A* on all 4. Please give me advice on what to do, as I am very lost. Thank you.