Gosman's at Montauk Dock is listed as being open "weather permitting" - I don;t know exactly what that means - but you are eating out over the water so I would expect it to be cold - and quite possibly closed You would have to check.
And this is on the far side of Montauk from Guerney's. Amagansett would probably be closer.
I just looked on opentable.com and at least 4 places are open. You should also take a look on yelp.com and perhaps call a few places. Or call the concierge at your hotel (Gurneys?) and ask for local recommendations. January is a tough month, as most places close & go on well deserved vacations in the winter.
I just called Harvest at Fort Pond for you and they,re open thru this Sunday and then close til Valentine,s day. They suggested calling the Montauk Chamber of Commerce who would have a list of places that will be open but I think the pickings will be slim at that time.Edited: 08 January 2018, 21:14
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