Agree with FFF and GB - (I generally do). I think it is better to keep up the momentum, leave the groundschool on the Friday afternoon - keep up the work over the weekend and then straight into the exams. I would not want to leave any sort of gap.
It is hard to define but I found an energy for the 3 weeks of brush ups and exams that I do not usually enjoy. I have only experienced the same once before and that was also in a situation where I was working in a very intensive learning environment. On both occasions I was working from around 8.30 to 24.00 each day and a little on the weekends and for some reason it felt great. Go with it.
By the way I think we all feel the same way about the brush ups. I certainly felt anxious about my knowledge of the material but in the end it was all fine. Strangely I am feeling the same anxiety now with Mod 2 even though I have been there once before and it was fine.
Good luck