I'm doing A2, Bio, Chem, And Maths, this question relates mostly to the Bio and Chem, does full on study (overnight) the day before the exam actually improve your performance? Of course I'm studying even before the Jan exam but will an overnight-er boost my performance? I will trial this during mock week, but just checking.
For me, it's the only thing that worked for GCSE but at AS it was no use and left me really tired in the morning. Certainly will not do this for my A2 Jan exams (Bio, Chem, and Eng) I think I shall get a good nights sleep (about 10 hours) for Bio and and Chem and then perhaps revise a little (about 30mins) in the morning.