I'm not sure but I'd recommend looking at your exam board specifications and brush up on anything you're not doing too well. And whilst your at it try to perfect your exam technique work on different ones see which one works best for you etc
Grade 8 and 9 are similar. The thing that separates is the work ethic between the two students. Grade 8's work hard but 9's work even more harder and go the extra mile So, lets say the teacher gives a class homework and asks complete 2 tables they may complete 6 I don't know if that makes sense but yeah.
*For english GCSE* I got 9s in english lit and lang. My advice is 100% to use Mr Bruff's grade 9 exemplar essays. They have words, terminology and historical contexts you may not have come across before but once you learn them and implement them into your essays then you have a much better chance of getting a 9.
Btw this advice is coming from someone who only used mr bruff videos so if you want to further increase your chances of getting 9s in english then use the other resources you may have for a broader perspective on the topic.