How many hours do you study every week for this paper (P4)?

Hello all
I am just trying the whole OT experience. I have only P4 left to sit in less than 2 month, my first attempt. I did so well last sitting i regret why i did not sit P4 as well. Now i am working full time and get home really tired. I sarted reading the text book recently but the week end i should be done with up to inverstment appraisal. I am freaking out because i think i will never have enought time prepare. Can one month do to get fully prepared by doing just the rev kit? any tips would be appreciated as well