Grade boundaries for ocr ideas in context.?

what are the grade boundaries like for ocr 21st century science unit 4 ideas in context exam? some how miraculously only dropped 2 marks on the year 10 one and got an A* on it which is amazing because i usually get high B/ low A in science. so will the year 11 one be pretty much just as easy? i have the exam on tuesday. so far only revised biology and a bit of physics and done none on chemistry yet but last year i barely revised at all and only did about 1.5 hours all together.