Be aware that no UK University routinely asks for 4 A levels at A2.
No they don't, not even Oxbridge.
And therefore, whilst its fine to do 4 AS, you will get no extra credit for attempting 4 at A2.
RG Unis score the top 3 and ignore anything else. Some even ignore AS levels or EPQs (yes, they do).
By doing 4 A levels to A2, you run the risk of getting BBBB instead of AAA, simply because you've attempted something as a 'clever' gesture that you didn't need to. How silly is that?