I have this same issue, but one step worse: I can't actually figure out HOW to create a new PDF, even if I am willing to pay for it (or, in my case, charge my client for it).
I've edited and re-uploaded the print book files, but the PDF still shows the original version. The "Order" page doesn't even give me an option to get a new PDF (see screen), and I don't see how to delete just the PDF and reorder it. I can't delete the entire project, because my client already had the link to order the print copies. But I can't figure out how to update the PDF once it's been created.