I work in education and I've attended quite a few union events and conferences. I was looking at the web page for the NEU's National Women's Conference, and found that it was for women-only, but for an 'inclusive' definition of women, as follows:
"All members who significantly identify as female. We use an inclusive definition of ‘woman’ and ‘female’ and we welcome trans women, genderqueer women, and non-binary people who are significantly female-identified."
I would have no problem with transsexuals attending a women's education conference - people with dysphoria who have had surgery. I'd also have no problem with the conference being open to everyone, including men, and it being a conference about women's issues in education rather than specifically for women.
As it is, it seems to include everyone who doesn't identify as a man. So woman = non-man. I can't support that, and I'm disappointed.