The ships slips may vary. It's hard to know exactly which slip a given will be in. Closer to departure ncl will notify. At times you may leave from one slip and return to another. (Pier 90 was hit by a Carnaval ship end of August and that slip was out of commission for a while.)
The Jade will be leaving from NY twice in Apr. of 2019, It will most likely leave from Pier. 88 as that's were most of the boats leave from.
I don't believe that one sails from NYC. We sailed on the Gem & Escape.
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