Quick reply to your suggestion that the C of E will screw women over later this year by saying a woman is anyone who identifies as one.
I don't think there's any possibility of that. It would have to be agreed by General Synod, the Church's governing body. At the last set of elections the makeup of Synod became more traditional in terms of those elected, not less.
Whatever you think of that in general, it means most Synod members take a fairly traditional view of biological sex as binary, and a sceptical view of gender self-ID etc.
The House of Bishops might well move closer towards blessing of gay marriages (I'd say that's likely, following the lead of some other Anglican provinces). But I reckon there's zero chance of Synod defining a woman as anybody who identifies as one.