Its 11am UK time I believe. And no you can make reservations for any of the parks or hotels or Disney Springs even without a park reservation. The issue with that is that if capacity is too high to allow you to enter the park on the day (say you are thinking of park hopping to the place where the restaurant is) you wont be able to enter and would be charged a no show fee for the restaurant. Although it is highly unlikely the park will be at capacity it is something to watch out for