Not sure but reservations aren't necessary.
One month
Family of 4 or smaller u can usually get in to eat in the lounge area with no reservations and u will b overlooking the restaurant. If u insist on the rotating restaurant. A day or two advance is ideal.
For large groups, three to four weeks is my recommendation, if not several months. For family or couples, Kathy is right: they are not usually necessary.
You do not need one
I agree with Kathy
Typically its up to a month.
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