Good question! I did a full brake service, removing pads and exercised the pistons (I had a lazy seal issue). The pistons were fully pushed back before installing pads and wheel. It seems possible that the caliber mounts where just loose enough for the force of pushing the pistons could have move the caliber. Visual inspection makes it look like the caliber body is too far in-bound, lot of pad showing on the outside and very little to the inside.

reference - lazy seal fix: