The FWS and SM submissions are wonderfully clear, logical and rational.
The GRA is not a master law that overrides all subsequent laws in case of any contradiction, nor is it a magical spell which transforms men into women.
I do hope that when arguing before their lord- and ladyships, our barristers point out that yet another bizarre consequence is that the combo of easy-to-obtain and confidential GRCs + grouping women plus men with GRCs is also useless for planning, whether it is toilet space or maternity wards.
As we have been saying, this grouping serves no purpose except to lump in an impossible to quantify number of males with women.
Also they should ram home that a male with a GRC can be an unaltered, beardy 6-footer, not the slight, small, homosexual male with full GRS that most MPs at the time probably had in mind as a "transsexual".
The Supreme Court judges need to ask themselves a version of the Staniland question:
Did the drafters of the EA2010 intend for a fully intact middle-aged man to have the right to share communal changing and showers with 13-year-old girls?