I don't believe in the whole hours thing, nobody can predict how long it takes you to get all the work done. I could say 5 hours but it might mean you won't cover everything.
Just take it topic by topic, that's how I do it, and that's why I don't have a revision timetable but my own self-made revision topic table. Do for example 3 Biology topics and 3 Business Study topics one day then next day do Maths past papers and 3 psychology topics and carry on in that pattern. Make sure that you finish everything, understand everything clearly and leave time to get past papers done before the exam. If you do the past papers with ease and hardly any thinking your revision was succesfull. To me it's what you get done, not how much time you spend getting something done.
Realistically I'm looking at 6 hours of work per day.