Form AN, enter biological father?

Hi guys,

trying to understand the requirements for details of parents. My father died in 1965 when I was two. My mother remarried soon after and i took his name (changed by deed). So do I enter details of my biological father, or my step-father? Thanks for any advice on this.

State the name of your step-father.

I managed to get through to the UKVI hotline yesterday. I was told that in my case details of biological parents are required. I also note from reading the instructions for completing a UK passport application that there is the same requirement i.e. details of biological parents.

I stand corrected if that's the case - however, I understand that parents' names are asked for in case the applicant may already be British due to parentage.