it was in 2012, it started with Dittany suggesting a name change for the single solitary FWR board.
It blew up from there, but the extra boards were created with Theory/activism supposedly being for the more hardline/RadFem posters, with FWR chat being left for everyone else just coming around to feminism and wanting to be able to chat without the yells of rape apologist, sex pozzie and other things that used to get thrown out there to shut down conversation.
Over the last two years, the mumsnet radfems have stopped using activism/theory and taken over Chat, so now, someone else is suggesting yet another 'femlite' forum for everyone else to use.
I didnt mean to be harsh at you.. its just that a new subboard wont change anything, they will once again, take over and push everyone out, because no-one is allowed to discuss feminism on mumsnet unless you proscribe to the accepted rad-fem view.