multiple rrdtool high (100%) cpu usage

We are a support company and we have several hundred devices with several thousand users. All of which are effected

Edit: All devices are running 9.714.004

All appliances are set to Europe / London. We have had to manually login via WebAdmin and force a reboot, which is painfully slow taking 10-15 mins per device due to 100% CPU usage on rrdtool (multiple instances)

On those devices that SSH is enabled, you can SSH in and..
su root
restart -r -t 1 now

to force a reboot

We have now been rebooting devices for over 10 man hours of support.

Please note we have not had to change the time zone on any device, those devices that have been rebooted are acting normally

Before Sophos Support came back to me as i was facing a complete outage, i followed the above of running the following commands on initially the slave node, followed by the master node. 

killall /usr/local/bin/create_rrd_graphs.plx
killall rrdtool

CPU dropped off immediately when both commands were run on both nodes

I didnt amend crontab as i wasnt seeing the rrdtool proccess respawn over an hour of monitoring the processes, and was prepared to re-run the 2 commands when needed.

Spoke to Sophos support 2 hours after logging call, and they recommended, change the timezone and reboot or kill rrdtool.

I am scheduling a change this evening out of hours to amend time zone to UTC and rebooting both nodes incase.

As per Thomas, the nodes seem to be ok at the moment, and time zone is still set to Europe/London.

Is this issue only present when daylight savings change, and on firmware 9.714-4?  Therefore the next potential issue would be in the autumn if you were running this firmware still or is the rrdtool process respawned automatically during the day and this then triggers multiple rddtool processes, unless you amend timezone to UTC?

Before Sophos Support came back to me as i was facing a complete outage, i followed the above of running the following commands on initially the slave node, followed by the master node. 

killall /usr/local/bin/create_rrd_graphs.plx
killall rrdtool

CPU dropped off immediately when both commands were run on both nodes

I didnt amend crontab as i wasnt seeing the rrdtool proccess respawn over an hour of monitoring the processes, and was prepared to re-run the 2 commands when needed.

Spoke to Sophos support 2 hours after logging call, and they recommended, change the timezone and reboot or kill rrdtool.

I am scheduling a change this evening out of hours to amend time zone to UTC and rebooting both nodes incase.

As per Thomas, the nodes seem to be ok at the moment, and time zone is still set to Europe/London.

Is this issue only present when daylight savings change, and on firmware 9.714-4?  Therefore the next potential issue would be in the autumn if you were running this firmware still or is the rrdtool process respawned automatically during the day and this then triggers multiple rddtool processes, unless you amend timezone to UTC?