The narrative around GRA reform is that the Equality Act remains unchanged and so women will still be able to access single sex spaces using the exemptions in the EA.
Now, apart from. Lady Haldene's recent court ruling throwing into question what the definition of 'sex' and 'woman' even means in law (biology or paperwork), and requiring urgent clarification, Stonewall have this on their website right now as one of their 'recommendations' to the Women and Equalities Select Committee:
A review of the Equality Act 2010 to include ‘gender identity’ rather than ‘gender reassignment’ as a protected characteristic and to remove exemptions, such as access to single-sex spaces
www.stonewall.org.uk/women-and-equalities-select-committee-inquiry-transgender-equality
At the moment, even those males with a GRC can be excluded from female only provision in certain situations. The above reads to me as though Stonewall want to remove those exemptions so that that would not be possible. If anyone is able to clarify this I would appreciate it.
Stonewall is the biggest 'LGBT' charity in the country, so this is fairly significant to me, even if its unlikely to ever be changed. I don't think they are going to stop until women do not have anywhere they can exist away from males.