In large bowl, combine all-purpose flour, whole wheat flour, cereal, sugar, baking soda, baking powder, salt, allspice and orange peel; mix well. Add buttermilk, oil and eggs; blend well. Stir in fruit bits. Cover tightly;refrigerate at least 3 hours or up to 2 weeks.
When ready to bake, heat oven to 400°F. Grease desired number of muffin cups or line with paper baking cups. Stir batter; fill greased muffin cups 3/4 full.
Bake at 400°F. for 18 to 20 minutes or until toothpick inserted in center comes out clean. Immediately remove from pan. Serve warm.