It doesn't matter how many hours you study. what matters is your way of studying.
prepare notes or write important points in the header or footer of that munish bandari book. You can have only one day before your exam, to revise. so, prepare notes and important points in such a way you can revise total syllabus in one day. Reading the book completely and not revising before exam is not good. So, revise.
Important points and notes will save lots of time while revising.
For example, if it takes 1hour for first time reading, it will take only 15 minutes for revising next time, if you prepare notes.