I'd look for the predictions. Having predictions of AAB from AS results of ABB is fine. So long as you're happy that's realistic and obtainable, and your teacher(s) agree and will offer that prediction then it's not going to cause you any problems. Universities know that it's not always a big jump from one grade to another, could have just been a bad day etc. Filtering out candidates below predicted grades is likely an easy start for some places, but it's hard to say exactly how much they look into it or pay attention to it.
Speak to your tutors for computing and physics - you need to decide what you think is possible first, and then i'd approach them for the prediction. If you were close to the A border with your total UMS then they're unlikely to have too many issues, and equally if you have a consistent class record (in-class assessments or previous submitted work at an A grade).