Coat a 9 x 13-inch glass baking dish with cooking spray; place bread cubes inside. Sprinkle blueberries on top. In a large bowl, beat Neuchatel cheese until smooth. Add sour cream, sugar, milk and syrup; beat until smooth. Add eggs, cinnamon and vanilla; continue beating until mixture is blended. Pour over bread and berries. Cover with foil and refrigerate several hours or overnight. Remove from refrigerator about 30 minutes before baking. Preheat oven at 350°F. Bake covered for 30 minutes. Uncover and continue baking until no signs of visible liquid egg or about 20-25 minutes longer. Sprinkle remaining blueberries on top and serve with additional maple syrup if desired. Refrigerate leftovers.