The events don't have listed end times, as far as I know. When we visited, the event didn't end until around 2am.
The Nuyorican Poets Cafe usually closes at around after 4am. It depends on how long the events and the performances would last according to their schedule. I visited the poets café and I attended a poetry event and it was crowded filled with a lot of people and I stood there until almost 1:00am.
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