I believe you can reserve almost immediately. In the case of the Grill, if you can find the maitre d' with his book, you can reserve. In the case of Apicius, I think there are hours when you can go by and make a reservation. You can do that the first night I think.
Wendy
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Booked: Uniworld Egypt, 2015
Tauck Amsterdam to Budapest, 2016
Paul Gauguin, Societies & Tuamotus 2016
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