The National Union of Students has long had a lesbian & gay section and conferences.
These days the conventional values in NUS circles are that the campaign and the conference alike are for lesbian, gay, bi, trans and queer students. In the 1980s though just as other sections of the gay liberation movement were struggling with bisexuality, so were the students. In 1987 a fractious national conference moved to expel bisexuals on the grounds that bi people carried heterosexual privilege and as such were basically straight.
The best compromise that could be achieved was to expel bis and call for them to self-organise separately and in parallel to the lesbian and gay conferences and organising.
We made our NUS comeback pretty quickly. Student groups tend to have an attention span of about three years, after all!