There may well be such a procedure that someone will share, or perhaps there's one here already. You can go to the top of the page and click on "Post Attachments List" and search from there.
It should be a fairly easy thing to do on your own, though. A simple spreadsheet that shows the due dates and actual completion dates will do. You don't say if your customer requires a
documented procedure. If they do, then it should also be fairly easy to document the process in a few lines.
One thing you have to be careful about is how reasonable the customer's expectations are, and what your company agrees to. If a customer says that a PPAP must be submitted by October 1, but you know that it's not going to happen by then, it doesn't help much to track completion dates. The chronology of the
APQP process, and the expected end date (when PPAP is submitted) should be a matter of negotiation, and if your management is writing checks that the system can't cash, everyone will be unhappy in the end.
What's an enquiry register?