Reapplying UCAS again - resitting A-levels - does prediction matter -

I am currently in my first year of university and applying to UCAS for a transfer. Since I am a first-year reapplicant, my application is primarily based on my A-level grades. I am also planning to resit one of the A-levels where I fell short of meeting my grades. In this context, do I need to be concerned about first-year predictions for my current university, especially considering I have exams in January? How does the prediction system work, and if I achieve a higher or lower second-class grade in the January exams, can I still potentially attain a first-class prediction by the end of the academic year?