Quick question re passport application????

[Ihaveafeeling]

As everyone here is always lovely and helpful I hope you can help.
If my child already has a passport in the BF name do I apply new passport as if they have never had one in their new adopted family name or do I apply as changes to their existing passport? I'm unsure how to complete the application and know there are more experienced adopters here who might be able to advise.
TIA x

We had to send back DD's existing passport. I remember that.

I think we had to put their birth names on the form somewhere.

I do also remember there was a very helpful person at the end of the passport office helpline.

We then used Post Office check & send service.