2 pounds ripe peaches, peeled, pitted, and thinly sliced
1 tablespoon fresh lemon juice
1/3 cup granulated sugar
1½ tablespoons cornstarch
1 teaspoon ground cinnamon, divided
½ cup whole-wheat pastry flour
1/3 cup rolled oats
¼ cup light brown sugar
2 tablespoons chilled salted butter, cut into bits
3 tablespoons frozen orange juice concentrate
¼ cup coarsely chopped walnuts
To make crust, whisk together flours in a medium bowl. Cut in butter and cream cheese with a pastry blender, mix until crumbly. Stir in oil, then orange juice; continue until dough comes together in bowl. Gather dough into a ball, knead a few times, and press into a flattened disk. Wrap in wax paper; refrigerate 30 minutes or overnight.
Place chilled dough between two large pieces of wax paper; roll into a 12-inch flat circle. Peel off top sheet of wax paper; transfer dough, wax paper side up, to a 9-inch deep-dish pie pan. Gently press dough onto bottom and up sides of pan. Peel off paper; crimp top edges of dough to form a rim. Prick dough in several places with a fork; refrigerate 15 minutes.
Preheat oven to 375°F. Bake crust 15 minutes; let cool.
To make filling, combine blueberries and peaches in a large bowl. Gently toss with lemon juice. Whisk together granulated sugar, cornstarch, and ½ teaspoon cinnamon in a small bowl. Pour over peach-blueberry mixture; toss to blend. Transfer fruit mixture to cooled shell. Coat edges of crust with nonstick cooking spray and bake pie about 25 minutes.
While pie bakes, make topping by stirring together whole-wheat pastry flour with rolled oats, light brown sugar, and remaining ½ teaspoon cinnamon in a medium bowl. Using a pastry blender, cut in butter until evenly distributed. Stir in orange juice concentrate and nuts. After pie has baked 25 minutes, remove from oven; scatter topping over fruit. Bake 20 minutes more or until juices are bubbly and thick around edges. Cool 1 hour before slicing into wedges.