In a large bowl, whisk eggs, milk, cinnamon, salt and pepper until blended. Stir in bread, prosciutto, apples, spinach, Brie and 1/2 cup cheddar cheese. Transfer to a greased 13x9-in. baking dish; sprinkle with remaining 1/2 cup cheddar cheese. Refrigerate, covered, overnight., Preheat oven to 350°. Remove strata from refrigerator while oven heats. Bake, covered, 30 minutes. Uncover and bake until a knife inserted near the center comes out clean, 20-25 minutes longer. Let stand 10 minutes before serving.