regression in the gnome-shell 'power' menu

This appears to be a regression from gnome-shell on 14.04. When I clicked on 'power button' -> user name I would see log out & switch users as options. When I do the same on 16.04 gnome-shell, I see only log out, no switch users option.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: gnome-session 3.18.1.2-1ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-4.19-generic 4.4.1
Uname: Linux 4.4.0-4-generic x86_64
ApportVersion: 2.20-0ubuntu2
Architecture: amd64
CurrentDesktop: GNOME
Date: Tue Feb 16 10:49:07 2016
InstallationDate: Installed on 2015-12-21 (56 days ago)
InstallationMedia: Ubuntu-GNOME 16.04 LTS "Xenial Xerus" - Alpha amd64 (20151220)
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-session
UpgradeStatus: No upgrade log present (probably fresh install)