I saw this Government Response to the Women and Equalities Committee Report on Transgender Equality on another platform today. This was the 2015-16 review that led to the abortive attempt to bring in self-ID, but take a look at Recommendation 12.
Recommendation 12
We recommend that the Equality Act be amended so that the occupational requirements provision and / or the single-sex / separate services provision shall not apply in relation to discrimination against a person whose acquired gender has been recognized under the Gender Recognition Act 2004.
https://assets.publishing.service.gov.uk/media/5a817d0ced915d74e62328a3/Government_Response_to_the_Women_and_Equalities_Committee_Report_on_Transgender_Equality.pdf
The government’s response makes it clear some groups were already offering services to men who claimed they were women, but whichever trans groups advised the Women and Equalities Committee at this stage 100% knew and accepted that men with a GRC could be excluded from single sex services.
The cynicism of their performance since then is off the scale.