A level/University/Predicted Grades

I've seen some student blogs online recently which depict their university admission experience etc. They mention how universities actually give them an offer around mid-January in year 13. They also mention that part of the acceptance is based on predicted grades that a student attains. Are these predicted grades formed based on GCSE or year 12 performance? I have a further 2 questions on this. (I hope you don't mind haha). If based on GCSE performance,will there be some sort of leeway in terms of university acceptance? By this I mean, will universities consider that fact that when that student was in year 11, the grade they achieved was not completely representative of their ability (as they didn't take the exam)? Also, if the predicted grades are based on year 12 performance, does that mean that year 12 attainment almost directly influences someone's admission into a university?
Thanks

Based on teacher assessment of what they think you will get.. Small but may be on GCSE, but much larger part on things like mocks. Talk to your teacher.

Most uni courses expect a grade of 5 or higher in core GCSE subjects, such as English and Maths. I don’t think it’s the ultimate decider at all- I know various people who didn’t do great at GCSE and still have places at uni. What really matters is A-Levels. From what I know, whatever you apply for, your most recent grades will be considered. So, GCSEs are considered for A-levels, a-levels for uni, and degrees for jobs. That’s not to say that other qualifications aren’t considered, but in my experience GCSEs don’t matter as much as you may think. If you have poor GCSE results, I wouldn’t consider it the end of the world. You can still go to uni. Think about it like this- a uni would rather take someone on with poor GCSEs and great a-levels than someone with great GCSEs and poor a-levels. A-levels are definitley harder and show your potential a lot more. As for the attainment, I’d say yes. Predicted grades are made by your teachers, and are based on how weThll you are doing at a particular time. When I started my a-levels, I was targeted a B in sociology, and this was lowered to a D when I missed a lot of time for health reasons, simply due to I’d missed a lot of work. I still got accepted into all Unis, and since I managed to turn around my learning by attending more and doing extra work, my grade will probably undoubtedly be much higher than a D, and my teacher agrees. Hope that makes sense. Overall I’d say- GCSEs are not the main consideration for uni, and there will undoubtedly be leeway. Focus in year 12 to achieve best attainment, but remember you can get offers even if your grades dip slightly. Best of luck!