Line bottom and sides of a 13- x 9-inch pan with heavy-duty aluminum foil or parchment paper, allowing 2 to 3 inches to extend over sides; lightly grease foil.
Preheat oven to 350°. Beat flour, butter, granulated sugar, oats, and brown sugar with an electric mixer until crumbly and mixture resembles wet sand. Reserve 1 1/4 cups mixture. Press remaining mixture onto bottom of prepared pan.
Bake at 350º for 20 to 22 minutes until light golden brown.
Meanwhile, microwave both jars of lemon curd at the same time at HIGH 1 minute or until pourable. Spread lemon curd over hot baked crust, and sprinkle with reserved crumb mixture.
Bake at 350º for 30 minutes or until bubbly and brown. Let cool in pan on a wire rack 30 minutes. Lift from pan, using foil sides as handles. Cool completely on a wire rack (about 30 minutes). Remove foil, and cut into squares.