Westminster have made sure of this by revising the list of countries whose GRCs they recognise and removed all that are obtained through self id which means that they can't be accused of singling out Scotland.
I didn't know that!
You may not be aware but holding and/or knowingly issuing a passport that doesn't accurately reflect your sex and/or name on your birth certificate, grc, depole documents or marriage certificate is a crime (why the civil service at the passport office do this and why no one has been prosecuted for it I can only guess
I wasn't aware of that, because the passport office are perfectly happy to change sex marker on a passport without a GRC.
https://www.gov.uk/government/publications/gender-recognition/gender-recognition-accessible#about-gender-recognition
"Unlike the gender recognition certificate (GRC) the issue of a passport in an acquired gender does not give legal recognition of the change of gender. For passport purposes, the question is only whether the person has permanently adopted a new identity.
We show the customer’s gender on the personal details page of the passport. It will not always match the gender recorded on their birth certificate, as there is no indication in the passport of the customer’s personal circumstances."
https://www.gov.uk/changing-passport-information/gender
says you only need a doctor's letter, evidence of name change (deed poll) abd evidence of use of new name (e.g. bill) to change the gender marker (as they call it) Though a GRC will also do the job.