NY 427 was extended northward along Pennsylvania Avenue to a new terminus at Water Street (NY 14 and NY 17E; later NY 352) as part of the change. At the other end of the route, the easternmost part of NY 427 was realigned  to follow Wyncoop Creek Road to a new interchange (exit 59) with the Southern Tier Expressway (NY 17) in Chemung.
NY 427 was extended northward along Pennsylvania Avenue to a new terminus at Water Street (NY 14 and NY 17E; later NY 352) as part of the change. At the other end of the route, the easternmost part of NY 427 was realigned  to follow Wyncoop Creek Road to a new interchange (exit 59) with the Southern Tier Expressway (NY 17) in Chemung.