Preheat oven to 350°. Line a 13- x 9-inch pan with parchment paper. Prepare angel food cake batter according to package directions. Pour batter into prepared pan.
Bake at 350° for 30 to 33 minutes or until a wooden pick inserted in center comes out clean. Cool in pan on a wire rack 10 minutes. Remove from pan to wire rack, and cool completely (about 30 minutes).
Meanwhile, coat cold cooking grate of grill with cooking spray, and place on grill. Preheat grill to 350° to 400° (medium-high) heat. Coat peaches with cooking spray, and grill, without grill lid, 2 to 4 minutes on each side until tender and slightly charred. Remove from grill, and let cool 5 minutes; cut into large pieces.
Microwave preserves in a large microwave-safe bowl at HIGH 30 to 45 seconds or until melted. Toss peaches and 1 1/2 cups blueberries with warm preserves. Stir in granulated sugar and next 2 ingredients.
Invert cake onto a cutting board. Carefully remove parchment paper, and discard. Trim and discard edges of cake. Cut cake into 32 equal pieces.
Beat whipping cream and lemon juice at medium speed with an electric mixer until foamy; gradually add powdered sugar, beating until soft peaks form.
Arrange about one-third of cake pieces in a 3-qt. trifle dish. Top with one-third of peach mixture. Repeat layers twice. Top with whipped cream. Cover and chill 1 hour. Top with remaining 1/2 cup blueberries just before serving.