according to the curriculum i can basically do or working on everything up to level 4. my rink offers skate uk lessons but i was thinking i'll take them when i'm more advanced to save money. however, if i do take up group lessons now, would they make me start at level 1 or could i immediately progress to a higher level?
Rinks all handle their group learning sessions differently so it's hard to say what your rink would do in terms of placing/progressing you. At my rink then they essentially run two classes in the same time slot: one that covers the level 1-4 material and another for the 5-8 material. This is mostly done out of practicality more than anything else, paying coaches to do eight different levels of classes would be expensive for the rink and, broadly speaking, the stuff in 1-4 is all around an appropriate level for new skaters that it gives the coach in charge just enough variety of activities that they can dip in wherever they fancy for each lesson, so, at least where I am, you don't necessarily learn the levels in the strictest of orders. The 5-8 group operates almost exactly the same, but they sometimes borrow exercises from the progression beyond level 8 (Skate Star Bronze-Gold levels) in order to keep things spicy in those groups.
If you were at my rink then I suspect that, at your current stage, they'd put you in the 1-4 group and you'd get bumped up as soon as the coach thought you were pretty competent on that stuff. Honestly, I doubt you'd find being made to redo some early stuff to be that big of a pain because you get a whole new perspective on how you can improve what you're already doing. Coaches can refine what you're doing because when you're working with new elements by yourself then it's hard to know what's "correct" when you don't have an expert on hand to point out little corrections and adjustments.
For example, I secretly taught myself the single loop jump in advance of doing it with my coach, so when we got round to it together then I was able to surprise her a bit with what I'd been working on, but after I'd figured out the basics of the jump then I still had no idea what I was meant to do in order to improve it by, say, adding power while maintaining control and consistency. The positioning I'd been using for the takeoff in my secret practising was acceptable, but the long term growth of the skill, particularly if I ever intended to move towards the double loop, required that I have a similar, but fundamentally refined, body position for it that I probably wouldn't have worked out if it hadn't been for her. Maybe I could've gleaned it from watching enough YouTube videos, but there's nothing like a live human that knows what they're on about and catering to your specific level of learning. This analogy can be stretched to basically any element of skating, even the really early stuff. For instance, you'll find that you'll be working and improving on your crossovers for a surprisingly long time to come yet! Every time you think "yeh, I know how to do those" then your coach will show you a way to make them generate more power and then you have to work on controlling that new speed, etc.
All that said, I appreciate your attitude towards the cost element, keeping a lid on the costs in this sport/hobby can be a challenge! My rink charges something like £41 a month for a weekly half hour group lesson and free entry to the public session that that lesson is held on, so it works out at £10.25/week, although the entry to that public session itself would normally be £8.20 for a standard adult, so you're paying just over £2 more than normal entry for the session and you're getting a half hour lesson on top of the session time, which I think is pretty good value.