Ubiquity fails to install Ubuntu MATE 16.10

[Martin Wimpress ]

Attempting to install Ubuntu MATE 16.10 daily for June 6th 2016 results in Ubiquity failing. These are the relevant lines from syslog:

Jun 6 11:25:46 ubuntu-mate /plugininstall.py: Exception during installation:
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: Traceback (most recent call last):
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 1778, in <module>
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: install.run()
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 78, in wrapper
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: func(self)
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 204, in run
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: self.configure_plugins()
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 570, in configure_plugins
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: self.run_plugin(plugin)
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 547, in run_plugin
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: "Plugin %s failed with code %s" % (plugin.NAME, ret))
Jun 6 11:25:46 ubuntu-mate /plugininstall.py: ubiquity.install_misc.InstallStepError: Plugin timezone failed with code 2
Jun 6 11:25:46 ubuntu-mate /plugininstall.py:
Jun 6 11:26:47 ubuntu-mate ubiquity: Gtk-Message: Failed to load module "overlay-scrollbar"
Jun 6 11:26:59 ubuntu-mate ubiquity: /usr/share/apport/apport-gtk:16: PyGIWarning: Wnck was imported without specifying a version first. Use gi.require_version('Wnck', '3.0') before import to ensure that the right version gets loaded.
Jun 6 11:26:59 ubuntu-mate ubiquity: from gi.repository import GLib, Wnck, GdkX11, Gdk

ProblemType: Bug
DistroRelease: Ubuntu 16.10
Package: ubiquity 16.10.1
ProcVersionSignature: Ubuntu 4.4.0-23.41-generic 4.4.10
Uname: Linux 4.4.0-23-generic x86_64
ApportVersion: 2.20.1-0ubuntu4
Architecture: amd64
CasperVersion: 1.376
Date: Mon Jun 6 12:26:47 2016
InstallCmdLine: file=/cdrom/preseed/ubuntu-mate.seed boot=casper only-ubiquity initrd=/casper/initrd.lz quiet splash --- keyboard-configuration/layoutcode=gb
LiveMediaBuild: Ubuntu-MATE 16.10 "Yakkety Yak" - Alpha amd64 (20160606)
ProcEnviron:
 LANGUAGE=en_GB.UTF-8
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)