Hi I was in NYC for a weekend and the tickets were sold out. However we did visit Chelsea market and they have a ticketing centre for Artechouse that we discovered accidentally not realising that this is where it is. We spoke to the lovely lady there who managed to book us a ticket for the day after the online reservations were full. So if you are really keen on going, on the first day in NYC visit their office and you can try your luck. It means traveling to the area twice which usually on a holiday in NYC you wouldn't want to do, but this is worth it. Who know you may get even more lucky and be able to get a ticket for the same day :)
It's by reservations. If it's sold out online, you can try and call to see if anyone has cancelled.
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