Preheat the air fryer to 350°F and lightly oil the basket with the neutral oil.
Stir the granulated sugar with 1 teaspoon cinnamon in a shallow bowl; set aside for coating.
Combine the chopped apple pie filling with the apple pie spice and the remaining 1/4 teaspoon cinnamon.
Flatten each biscuit into a 3–4 inch round. Spoon about 1 tablespoon apple filling in the center.
Pinch seams to seal tightly and shape into a smooth ball with the seam tucked underneath.
Brush each ball with melted butter, then roll in the cinnamon sugar to coat all over.
Arrange bombs seam-side down in the basket, leaving space. Air fry 8–10 minutes until deep golden.
Whisk powdered sugar, milk, and vanilla until smooth. Let bombs cool 3 minutes, then drizzle with glaze and serve.