If you've used our Design online option and then made changes to your artwork, (after viewing a digital proof) you may see a "lag" in the image updating in the 3D view.
You can click on the submission method on the left side of the page and then regenerate the proofs by clicking save and continue until you get back to the actual proof page. The 3d viewer should now show the updated images.
We will always print from the PDF proof so as long as they are correct, you should be good to go.