Hi Kat
I called the passport telephone helpline and asked them to look into it (after 11 days of the documents being received). They noticed 2 birth certificates had been scanned into one application. They raised a “case” with another team. They called me back the next day and sorted it there and then on the phone.
give them a call. Also mention that you have a travel date booked and they can add it to the application, they said it may help speed it up. Best of luck.