A-level Software Systems Development or Physics?

Single award science won't be an issue other than perhaps a few topics in chemistry that might be applicable. So called "triple science" is just students taking all three single award sciences. Double award sciences actually covers less over the three topics than each single award, and since unless your school has a different structure double award sciences is the only assumed prior knowledge for A-level sciences (and you won't need any of the material from GCSE Biology and very little form GCSE Chemistry for A-level Physics), it shouldn't make any difference.

I would note that computer science courses in the UK (and related degrees in computing, IT, software engineering, etc) normally do not require any prior programming experience or an A-level in CS or a similar subject. Many if not most applicants to those degrees (except for the few that do require that subject, which are very few and far between - Cardiff is the only notable uni I can think of that requires it) have no prior experience in the subject. Normally the only required subject is A-level Maths (with A-level FM being heavily preferred by the likes of Oxbridge, Edinburgh, Imperial, Warwick, etc).

In actual fact A-level Physics would give you more options than an A-level in a computing subject, as A-level Physics is normally required (along with A-level Maths) for almost all engineering degrees (including electronic/information/computer systems engineering, as opposed to CS which does not require A-level Physics), as well as physics degrees. A-level Physics is also generally the more relevant/useful subject for most mathematics degrees in the UK (which usually include some applied maths content that builds on the kinds of topics done in A-level Physics, although the knowledge isn't presupposed).

Single award science won't be an issue other than perhaps a few topics in chemistry that might be applicable. So called "triple science" is just students taking all three single award sciences. Double award sciences actually covers less over the three topics than each single award, and since unless your school has a different structure double award sciences is the only assumed prior knowledge for A-level sciences (and you won't need any of the material from GCSE Biology and very little form GCSE Chemistry for A-level Physics), it shouldn't make any difference.

I would note that computer science courses in the UK (and related degrees in computing, IT, software engineering, etc) normally do not require any prior programming experience or an A-level in CS or a similar subject. Many if not most applicants to those degrees (except for the few that do require that subject, which are very few and far between - Cardiff is the only notable uni I can think of that requires it) have no prior experience in the subject. Normally the only required subject is A-level Maths (with A-level FM being heavily preferred by the likes of Oxbridge, Edinburgh, Imperial, Warwick, etc).

In actual fact A-level Physics would give you more options than an A-level in a computing subject, as A-level Physics is normally required (along with A-level Maths) for almost all engineering degrees (including electronic/information/computer systems engineering, as opposed to CS which does not require A-level Physics), as well as physics degrees. A-level Physics is also generally the more relevant/useful subject for most mathematics degrees in the UK (which usually include some applied maths content that builds on the kinds of topics done in A-level Physics, although the knowledge isn't presupposed).

Single award science is just one GCSE in science, so I wouldn’t have covered in as much depth in physics as the Double Award students or triple award students (triple award wasn’t offered in my school), so I would be significantly behind the rest is my problem.

No, you don't understand - "triple award" science, is students taking each individual single award science. So single award physics, single award biology, and single award chemistry, all together - this is what people call "triple award" science. It's not 3 GCSEs worth of a single science, that doesn't exist. Double award science is a single course where you earn two grades, and you cover all three sciences. You will have done as much physics as someone doing "triple science" (and more than someone doing double award), you just won't have done as much biology or chemistry. You literally have done as much physics as is possible to do at GCSE.

Of course, you won't have a broader GCSE science education, which might make you less familiar with some general principles of experimental work and writing up labs, and there are some topics in chemistry which are relevant to A-level Physics (mostly about materials and their properties and models of the atom, and relative strengths of different kinds of bonding). However you should be able to pick up the lab stuff quick enough and you just need to make a point of spending some extra time on those less familiar topics in A-level.

Sorry, I’m just finding this all a bit confusing, bear with me - I did sit a chemistry exam and physics exam, I was half way through my biology course before lockdown, the exams I did (SA Chemistry and SA Physics), the two contributed towards my overall A*, I only have 1 GCSE in science and then the other GCSE in a different subject compared to my class who have 2 GCSES in science.

That sounds like you were doing combined science, and it was just interrupted and you only got a partial award...I'd suggest you speak with your teachers to understand what qualifications you were actually sitting. However even if you were only doing combined science but were only examined on the physics and chemistry portions, that is still the "standard" amount of prior knowledge in the individual subjects expected by the exam boards for A-level students. Individual schools might expect students to be doing triple award to continue to A-level(s) in those subjects, but if your school didn't offer it then they will only assume as much as is in combined science. Also the GCSE Biology content is essentially entirely irrelevant to A-level Physics anyway. I don't know why you believe you are somehow behind but if your school didn't offer triple award science and you are continuing to A-level Physics there, and you covered all of the physics content in GCSE combined science before the lockdown, then you have literally done as much physics as they will expect.

So do you think from knowing that I did combined science, I should still do A level physics with the better teacher and A LOT more resources but more catching up with work or should I do SSD with possible not as many resources (no textbooks and 1 or 2 sets of past papers) and not as good of a teacher but possibly easier if I miraciously got the grips of it. My SSD class only has 2 in it so I would be getting more 1 on 1 attention but the physics is still a reasonably small class too, (with 9 in it). Also, would the lack of resources be an advantage in that grade boundaries could be lower because the entirety of people sitting SSD under that exam board wouldn’t have resources or would my no-so-great teacher still be a disadvantage if there are better teachers in other schools?

I mean, which do you actually want to study more? Which do you find more interesting?

My perspective is, your physics background is fine and won't make any difference in getting a good grade in A-level Physics, and having a good teacher is also a great thing. If you absolutely hate physics and never want to do it again then there's little point entertaining the idea - although that doesn't seem to be the case for you. Your only reservation with physics seems to be your belief that you somehow have not enough background in it, which I don't believe is actually the case.

Im not exactly sure what I want to further study but from the courses I’m looking at I would be roughly (with small 1 up or 1 down with a grade) looking 3A’s and I don’t want to risk that so I am trying to keep options open at the moment but from your point earlier, do you really think that physics could open more doors?

there's an a-level in software development now?

Well it will certainly give you more possible options - namely, any physics or engineering degree. Of course, the majority of engineering (and many physics) courses are also available with a foundation year for those who didn't take the required subjects to A-level, but if you have the option to take physics and want to keep that realm open you might as well. As indicated, for courses focusing on computer hardware (variously named electronic, information, or computer systems engineering) A-level Physics is usually required (although there are a couple of exceptions).

From the courses I’m looking at I would be roughly (witha small 1 up or 1 down with a grade) looking 3A’s and I don’t want to risk that with a lack of resources as I would be more of a logical thinker who would like repetition and textbooks and past paper questions and would find that would work better with me than just teacher resources on there own. At the end of the day, I would like a subject that I would be confident in getting the best grade possible and opens the most doors for after a levels. Would you be siding with the physics then for me when considering all these factors?