Is Maths and further maths A level possible in one year?

I appreciate the honesty, and I think the best course of action is just to start brushing up on my maths and dabbling in some of the a level content also. If I hypothetically go through with this, would it be better to do start learning A level maths first, and then going on to further maths, or would it be better to learn them simultaneously, to help prepare for predicted grade assessments.

Also for the predicted grades I would have sign up for a course at a college or online college, where I would sit exams to get my predicted grades for both Maths and further maths A level, I would theoretically have to sit them late enough to have covered enough content, and early enough to get an application out in time, but regardless it would be quite challenging getting the predicted grades for my application

I'm sorry, but I don't really see this plan as workable. One of the things about maths is that everything tends to build on previous topics, and there's a considerable gap between "I scrambled through the textbook to cover topic X quickly" and "If I'm doing topic Y and I need to do use topic X, I can recognize that's what I need to do and do it".
I'm really struggling to see how someone could write an exam that you took early enough for your application needs and could still reasonably predict your grades for June 2025 exams. For sure, the college would need to do something "custom" for your particular scenario, and even then, I think it's a massive reach. [A lot of students hit a "oh, this has suddenly got hard" wall after about the first year of the A-levels, when you start hitting things like integration and vectors. To a significant extent, it's what differentiates the B-grades with the A/A* grades. And you won't have even reached those topics at that point].
Sorry to be negative without a positive suggestion, but I can't see how you'd make this work. I think your only option would be to personally impress the college so that they're prepared to predict you the grades "on trust", and that seems a massive ask.
[Disclaimer: I'm not thoroughly knowledgable about the current application process - maybe I'm missing a trick].

Would doing the by the end of the year be more feasible? And if so, would the AS even allow me to apply to courses such as imperial, UCL or Cambridge for computer science?

Would doing the by the end of the year be more feasible? And if so, would the AS even allow me to apply to courses such as imperial, UCL or Cambridge for computer science?

When do you think the important dates are etc? The last ucas date is around mid jan and assuming it could be arranged (big assumption), you could get predictions around dec when, in theory, youd have covered ~ 5 months of work so roughly half m/fm. Obv, there are a lot of if/buts/maybes ... behind this.

Thanks for the reminder on this; my child's school has made them get everything done by about mid November, so I'm possibly being a bit pessimistic about how late you can leave things.

Would doing the by the end of the year be more feasible? And if so, would the AS even allow me to apply to courses such as imperial, UCL or Cambridge for computer science?

Im not really sure what youre thinking of but youd not be able to apply to comp sci cambridge when you were doing m/fm, mainly because its got an earlier deadline of mid oct and theres no way youd be in a position to apply. Youd have to get m/fm then apply the following year. However, its horribly competitive 20-1 in some colleges, for the last couple of years. Imperial has a similar reputation hence the comment about it being aspirational in a previous post.
Tbh, while dfranklin is rightly raising potential problems etc and really you should think about how theyd be sorted next year (so before june), Id put a bit of time in over christmas skilling up your maths gcse. So there are free and paid for bridging guides like
https://mathematicsforstudents.files.wordpress.com/2019/06/373371-bridging-the-gap-between-gcse-and-as-a-level-mathematics-a-student-guide.pdf
which you can work though, then maybe try the recent gcse papers. If by the end of jan say (or feb depending on what sort of plan you have), youre hitting 8/9 on a years worth of unseen exam papers youve got over the first small hurdle. Note there are other bridging guides, just google.
But Id really recommend having someone on hand to discuss stuff with. Even if its just motivation/planning/...

So should I just get stuck in with the actual A level content like the other guy said, or just do the GCSE A-level bridging, and I think my have to sit down with my old maths teacher and talk to him about what I could do.

I'm currently undertaking A levels in English literature and economics, and a Btec in music. I'm planning to take a gap year next year, and hopefully doing maths A level and further math A level in one year. However I won't wait till September to start, but will begin essentially straight after my year 13 exams. Is doing both maths A level and further math A level in one year possible, if so does anyone have any advice for this. I want to hopefully apply for computer science next year, and end up hypothetically at imperial or an elite university, would this be feasible? Cheers