BuddyPress.org

I’ve just woken up to find an auto-update to BP 12 has completely broken groups functionality on a client site. E.g. the main groups page is now post type ‘buddypress’ instead of ‘page’, so it’s no longer in the main nav. Lots of others breakages.

I need to roll back to the previous version. Presumably this involves doing more than rolling the plugin itself back, as 12 seems to have made loads of changes to the DB without consent. Please advise.