1. Preheat oven to 375°.
2. Combine first 4 ingredients in a large bowl, stirring with a whisk. Gradually add juices, stirring with a whisk until cornstarch dissolves. Add cranberries; let stand while preparing apples.
3. Peel, core, and cut apples into 1/4-inch slices to measure 9 cups. Add apples to cranberry mixture, stirring to coat. Pour apple mixture into a 13 x 9–inch glass or ceramic baking dish coated with cooking spray.
4. Weigh or lightly spoon baking mix into a dry measuring cup; level with a knife. Combine baking mix and next 3 ingredients in a medium bowl. Add butter, tossing with a fork until crumbly. Sprinkle oat mixture over apple mixture. Cover with foil.
5. Bake at 375° for 40 minutes. Uncover and bake an additional 15 minutes or until filling is bubbly and topping is brown and crisp. Cool on a wire rack 15 minutes. Serve warm.