Corporation Tax changes

First of all, I have to admit I did not do any online research on that but only checked the acca published document on changes to the syllabus for September sitting onwards. However, below is my query.

I was self studying from the book with rates valid until the June 2016. I knew the rates will change from this sitting but thought of reading acca update on the changes and was confident that in the exam can just use new rates given in the first few pages. But I have to say, half way through the q1 i realised corporation tax rate was flat of 20% and nothing about marginal rate or standard fraction. It threw me slightly off, making me think that not just the rate changed but the whole way the ct is computed. Can anyone confirm that? Are there still upper and lower limits? That would probably save me few points and any chances of passing.