Preheat oven to 325 degrees F (165 degrees C). Grease a 9x11-inch baking pan and line with parchment paper.
Heat dates, orange juice, and lemon juice in a large saucepan over medium-low heat, stirring often, until dates are soft, about 6 minutes.
Stir whole wheat flour, oats, brown sugar, baking powder, baking soda, and salt together in a large bowl; stir in melted butter. Press half of the oat mixture evenly into the prepared pan.
Spread date mixture evenly over oat mixture; sprinkle remaining oat mixture evenly over date mixture and press down lightly.
Bake in the preheated oven until golden, about 20 minutes. Allow to cool in the pan to room temperature, about 30 minutes. Refrigerate until chilled before cutting into squares, about 1 hour.