Hi there,
I just sent the documents for my two children’s first British passports. I supplied all the documents the website told me to (their birth certificates, their UK consular birth registration certificates, photocopies of one child’s US passport (the other child doesn’t have one yet) parent birth certificates, grandparent birth and marriage certificates). I just found this government website below, which is indicating I should have sent more documents to verify their identities and place of residence, but this is more than the checklist that the website generated for us required. Are we in trouble?
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1093084/OS_Guidance_G3_07.22.pdf
FWIW I sent both sets of documents in one envelope and only included the baby’s reference number in the address. They acknowledged receipt of the baby’s documents on 27 July and of the toddler’s documents today 1 August, so they must have opened the envelope.