@jingles still suffering from this; even with my firewall disabled:

● ufw.service - Uncomplicated firewall
   Loaded: loaded (/lib/systemd/system/ufw.service; enabled; vendor preset: enabled)
   Active: inactive (dead) since Sun 2017-10-29 23:35:18 GMT; 7min ago
     Docs: man:ufw(8)
  Process: 15919 ExecStop=/lib/ufw/ufw-init stop (code=exited, status=0/SUCCESS)
  Process: 337 ExecStart=/lib/ufw/ufw-init start quiet (code=exited, status=0/SUCCESS)
 Main PID: 337 (code=exited, status=0/SUCCESS)

Oct 29 23:35:18 tim-573P.m1.manifest.co.uk systemd[1]: Stopping Uncomplicated firewall...
Oct 29 23:35:18 tim-573P.m1.manifest.co.uk systemd[1]: Stopped Uncomplicated firewall.
Warning: Journal has been rotated since unit was started. Log output is incomplete or unavailable.

then syslog contains:

23:46:57 tim-573P gnome-shell[2404]: [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead
Oct 29 23:47:00 tim-573P gnome-shell[2404]: message repeated 7 times: [ [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead]
Oct 29 23:47:01 tim-573P gnome-shell[2404]: [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead
Oct 29 23:47:13 tim-573P gnome-shell[2404]: message repeated 25 times: [ [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead]
Oct 29 23:47:13 tim-573P NetworkManager[1318]: <info>  [1509320833.9569] audit: op="connection-activate" uuid="a3732481-3cb7-4d38-8742-f63da6e56544" name="Manifest" pid=16231 uid=1000 result="success"
Oct 29 23:47:13 tim-573P NetworkManager[1318]: <info>  [1509320833.9657] vpn-connection[0x563edd4c62d0,a3732481-3cb7-4d38-8742-f63da6e56544,"Manifest",0]: Started the VPN service, PID 16479
Oct 29 23:47:13 tim-573P NetworkManager[1318]: <info>  [1509320833.9748] vpn-connection[0x563edd4c62d0,a3732481-3cb7-4d38-8742-f63da6e56544,"Manifest",0]: Saw the service appear; activating connection
Oct 29 23:47:14 tim-573P NetworkManager[1318]: <info>  [1509320834.0030] vpn-connection[0x563edd4c62d0,a3732481-3cb7-4d38-8742-f63da6e56544,"Manifest",0]: VPN connection: (ConnectInteractive) reply received
Oct 29 23:47:14 tim-573P NetworkManager[1318]: <info>  [1509320834.0098] vpn-connection[0x563edd4c62d0,a3732481-3cb7-4d38-8742-f63da6e56544,"Manifest",0]: VPN plugin: state changed: starting (3)
Oct 29 23:47:14 tim-573P pppd[16483]: Plugin /usr/lib/pppd/2.4.7/nm-pptp-pppd-plugin.so loaded.
Oct 29 23:47:14 tim-573P NetworkManager[1318]: Plugin /usr/lib/pppd/2.4.7/nm-pptp-pppd-plugin.so loaded.
Oct 29 23:47:14 tim-573P pppd[16483]: pppd 2.4.7 started by root, uid 0
Oct 29 23:47:14 tim-573P NetworkManager[1318]: ((src/devices/nm-device.c:1452)): assertion '<dropped>' failed
Oct 29 23:47:14 tim-573P pptp[16488]: nm-pptp-service-16479 log[main:pptp.c:353]: The synchronous pptp option is NOT activated
Oct 29 23:47:14 tim-573P systemd-udevd[16487]: link_config: autonegotiation is unset or enabled, the speed and duplex are not writable.
Oct 29 23:47:14 tim-573P NetworkManager[1318]: <info>  [1509320834.0175] manager: (ppp0): new Generic device (/org/freedesktop/NetworkManager/Devices/11)
Oct 29 23:47:14 tim-573P pppd[16483]: Using interface ppp0
Oct 29 23:47:14 tim-573P NetworkManager[1318]: Using interface ppp0
Oct 29 23:47:14 tim-573P NetworkManager[1318]: Connect: ppp0 <--> /dev/pts/1
Oct 29 23:47:14 tim-573P pppd[16483]: Connect: ppp0 <--> /dev/pts/1
Oct 29 23:47:14 tim-573P NetworkManager[1318]: <info>  [1509320834.0292] devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
Oct 29 23:47:14 tim-573P NetworkManager[1318]: <info>  [1509320834.0298] device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found.
Oct 29 23:47:14 tim-573P gnome-shell[2404]: [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead
Oct 29 23:47:16 tim-573P gnome-shell[2404]: message repeated 5 times: [ [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead]
Oct 29 23:47:17 tim-573P gnome-shell[2404]: [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead
Oct 29 23:47:44 tim-573P gnome-shell[2404]: message repeated 55 times: [ [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead]
Oct 29 23:47:45 tim-573P pppd[16483]: LCP: timeout sending Config-Requests
Oct 29 23:47:45 tim-573P NetworkManager[1318]: LCP: timeout sending Config-Requests
Oct 29 23:47:45 tim-573P NetworkManager[1318]: Connection terminated.
Oct 29 23:47:45 tim-573P pppd[16483]: Connection terminated.
Oct 29 23:47:45 tim-573P NetworkManager[1318]: <warn>  [1509320865.0489] vpn-connection[0x563edd4c62d0,a3732481-3cb7-4d38-8742-f63da6e56544,"Manifest",0]: VPN plugin: failed: connect-failed (1)
Oct 29 23:47:45 tim-573P NetworkManager[1318]: <info>  [1509320865.0513] vpn-connection[0x563edd4c62d0,a3732481-3cb7-4d38-8742-f63da6e56544,"Manifest",0]: VPN plugin: state changed: stopping (5)
Oct 29 23:47:45 tim-573P NetworkManager[1318]: <info>  [1509320865.0514] vpn-connection[0x563edd4c62d0,a3732481-3cb7-4d38-8742-f63da6e56544,"Manifest",0]: VPN service disappeared
Oct 29 23:47:45 tim-573P NetworkManager[1318]: <info>  [1509320865.0550] devices removed (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
Oct 29 23:47:45 tim-573P gnome-shell[1840]: Removing a network device that was not added
Oct 29 23:47:45 tim-573P pppd[16483]: Terminating on signal 15
Oct 29 23:47:45 tim-573P NetworkManager[1318]: Terminating on signal 15
Oct 29 23:47:45 tim-573P NetworkManager[1318]: Modem hangup
Oct 29 23:47:45 tim-573P NetworkManager[1318]: Child process /usr/sbin/pptp 77.44.84.210 --nolaunchpppd --loglevel 0 --logstring nm-pptp-service-16479 (pid 16486) terminated with signal 15
Oct 29 23:47:45 tim-573P pppd[16483]: Modem hangup
Oct 29 23:47:45 tim-573P pppd[16483]: Child process /usr/sbin/pptp 77.44.84.210 --nolaunchpppd --loglevel 0 --logstring nm-pptp-service-16479 (pid 16486) terminated with signal 15
Oct 29 23:47:45 tim-573P pppd[16483]: Exit.
Oct 29 23:47:45 tim-573P gnome-shell[2404]: Removing a network device that was not added
Oct 29 23:47:45 tim-573P gnome-shell[2404]: [AppIndicatorSupport-WARN] Attempting to re-register :1.65/org/ayatana/NotificationItem/multiload; resetting instead