Gap year retake potentially increasing required grades

Hello,

I finished my A-Levels, but I missed an A in Physics by 4 UMS (476/480). I am currently on a gap year. Should I retake module(s) to get an A, or will Universities look down on the 3 year A-Level?

When retaking, I have two choices:

1. Retake an AS module, in which I got a B in, which would be very safe to bump my grade to an A, as the exam is really not that hard and A2 builds on it.

2. In one of my A2 units, I got 137 out of 150 UMS, which is A* territory, whilst in the other unit I got a B. I could retake my A2 unit, where if I do well, I could get an A*. Will the universities raise their entry requirements so much that they would want me to get an A*, possibly making it a better choice to retake only the AS module to get offers no higher than an A?

Thank you