It ‘s impossible to assess; your present level is what matters most; if you’re starting from scratch I’d say one to two hours is not enough; the sample texts are in average French, containing no recherché vocabulary; however the connections to be made between words, as asked by the examiners, are rather difficult; this other task required from the test taker, the rephrasing of whole parts of sentences requires a lot of experience in order to come up with idiomatic equivalents that’ll match the original formulation; those are two of the elements I noticed in those tests. It depends also on how fast you learn and on the learning method; there haven’t been as yet any magic tricks: learning a language is a difficult task.

You might try this self imposed schedule of yours and see what happens; you’ll have the results of a first test so as to go at it again with a better idea of what you need.