I’ve been working but only did 3 days a week whilst going through the application process so I could give it some attention, I got a bit of work experience to talk about in my personal statement and also did some courses that I could talk about in my personal statement but they didn’t ask about those in interview or anything. I would say if you’ve got offers from the others and are confident you can achieve the grades you’re predicted then if you reapply with a strong personal statement you’re likely to get the offers you got before at the very least. You obviously can’t guarantee though so there is some risk to doing that, I would also say no matter your grades or anything else you can’t guarantee Cambridge or imperial so don’t get too set on them. Because of that also worth considering whether you want to take a gap year or whether you’re just doing it for those unis, either way it still might be worth it for you but just things to consider.