I'm wondering if the delay would be caused by sizing issues with the box. Being a graphic designer myself, I know that things like that are most often created before a product is finished. And if the product dimensions are different that what they specced out then they will have to make adjustments to not only the size of the box but the artwork as well. I would assume if their designers are even halfway competent that resizing artwork for a box should take only a few hours at most. From the actual box production standpoint though it can take much longer, including creating new dies to cut the new box dimensions. Which in turn the box manufacturer has to send the artist new files for the die placement before the artist can actually resize anything. In my experience that can take awhile, logistically speaking.
Just a thought I had.
Just a thought I had.