I m not sure about dedicated transport but you can take C or E train & get off at 50th st station and walk to pier 88/90/92; alternatively take bus M42 & get off at 42nd & 12th then walk to pier 88/90/92. Sorry if this wasn't helpful as i know this is not what u were looking for....
Not to my knowledge. That is, to say, I have never seen any. I did a quick Google Search, and the Carnival Cruise pier is on West 55th Street and 12th Avenue. Port Authority is located on West 42nd Street and 8th Avenue. I would imagine Carnival Cruise Lines figures more people would take a cab to the pier than a dedicated bus line.
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