Assignment does not respect groupmembersonly setting

Set enablegroupmembersonly to true in admin settings (experimental). In a course with a number of groups and groupings: 1. Create an assignment. 2. Set Common module settings 'Grouping' = one of the groupings in the course. 3. Tick 'Available to group members only'. 4. Navigate to /mod/assign/view.php?id=#&action=grading 5. In the 'Separate groups' drop down select 'All Participants' 6. Only students within the grouping should show. (unless there are users with accessallgroups + submit capabilities who will be shown in the 'default' group).