You'll have to check the lirr schedule . Pick up a time line schedule at any railroad station if you can't find that particular schedule then ask the attendant at the ticket window.
Since this past Monday Amtrack start wprking on their tracks and impact the train service for long island and other lanes in the city ; best to do is contact Ronkonkoma train station to be more specific with your trip
Called LIRR no trains from Ronkonkoma Line on Saturday, have to take the bus to HIcksville or use another line.
There is always track work
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