Preheat the oven to 350 degrees, and line a cupcake pan with cupcake liners.
Beat the cake mix, water, oil, and eggs in a large bowl or bowl of a stand mixer for 3 minutes.
Divide the batter between 24 cupcake liners, filling them just over halfway.
Transfer the pan to the oven, and bake for 9 minutes, or until a toothpick inserted into the center of the cupcakes comes out clean.
Remove cupcakes from the oven and cool for 1 hour.
In a medium bowl, stir together the flour, oats, brown sugar, sugar, cinnamon, and butter. Spread onto a parchment lined baking sheet, and bake at 350 degrees for 15 minutes.
Crumble once cooled.
Cut any of the large peaches into smaller pieces.
Once the cupcakes are cooled, add the frosting to a piping bag equipped with the 1A frosting tip, and pipe frosting around the edge of the cupcake, leaving the center hollow.
Add a spoonful of the crumble mixture to the center of each cupcake. Top with a bit of the peach pie filling, then sprinkle with a bit more crumble topping.