Preheat the oven to 350 degrees F (175 degrees C).
Pour blueberry filling in a 9x9-inch baking dish and smooth to even out in the dish. Sprinkle dry cake mix over the filling, smoothing evenly to cover the top. Sprinkle with oats and almonds.
Pour melted butter over the top, covering evenly. Mix sugar and cinnamon in a small bowl; sprinkle evenly on top.
Bake in the preheated oven until filling is bubbly and top is brown, 40 to 50 minutes.