Marlow,
To the best of my knowledge you'll be flying most days at least once, maybe twice. You will be expected to study in the evenings to get ready for the next days activities. It'll be busy but a good taste of what the real course will be like.
If you still need to prepare for the OSB whilst you're at the FSP then you are NOT ready for the FSP. Remember, Prior Preparation Prevents Pitifully Poor Pilot Performance.
WW