It's been highlighted before on here that the accurate definition of words is a main part of the problem when looking at the sex/gender debate.
Stonewall, a major source of information to the great and the good, it seems, has a Glossary of Terms:
www.stonewall.org.uk/help-advice/glossary-term
including the following
Lesbian: Refers to a woman who has an emotional, romantic and/or sexual orientation towards women.
Transgender woman: A term used to describe someone who is assigned male at birth but identifies and lives as a woman. This may be shortened to trans woman, or MTF, an abbreviation for male-to-female.
But the definition of the word 'woman' (or 'man' or 'male' or 'female') has not been included. Interesting omissions. And why would anyone have challenged it? We all know what a man and a woman is, don't we?
Careless or disingenuous?
Homosexual: This might be considered a more medical term used to describe someone who has an emotional romantic and/or sexual orientation towards someone of the same gender. The term ‘gay’ is now more generally used.
NB: "To the same gender", not same sex. Extraordinary.
Careless or disingenuous?
So it is hardly surprising that official bodies, such as councils, get in a sex/gender conflation muddle when writing their own policies with such inaccuracies as guidance.
An accurate official glossary would seem to be a good starting point.