Spray a 9 x 13-inch baking dish with nonstick cooking spray.
Cut the bread into 1-inch thick slices and lay the slices in the baking dish to cover the bottom.
In a medium bowl, beat the eggs with the sugar and vanilla. Stir in the milk and mix well.
Pour the mixture over the bread in the baking dish, turning the slices to coat. Cover and refrigerate overnight.
In a small bowl, combine the flour, brown sugar, and cinnamon. Cut in the butter with two forks or your fingers until the mixture resembles coarse crumbs. Cover and refrigerate.
In the morning, heat the oven to 375 degrees.
Turn the bread slices over in the baking dish, scatter the blueberries over the bread, and sprinkle it with the reserved crumb mixture.
Bake it for 50 minutes to 1 hour until it is golden brown. Allow it to cool for 10 minutes and cut it into squares to serve.