Child First Passport - Additional Documents Delay

Another very stressed applicant here. My application was started 03 March 2022. I received a message from passport office 27 March requesting the fathers birth certificate. The additional document was sent asap at the beginning of April. My application hasn't been updated so I have spoken to the advice line and was informed that the fathers birth certificate was received 27th April and has not yet been scanned on to the system so nothing can be done with regards to the passport application because the assessor cannot view the new information. To me this is the unacceptable part of this process. I was advised that the scanning of the document onto the system can take THREE WEEKS! Therefore I cannot do or say anything until 18th May because that is three weeks since the passport office registered the receiving of the documents. The best bit was the advice line told me the 10 weeks processing period will start from the date of the additional documents being received - 27th April. Surely this can't be correct. We are supposed to travel Monday 23rd May but this is looking highly unlikely. Any advice on how to get a document scanned, who to talk to etc would be greatly appreciated. Thank you in advance.