Since Thursday morning it seems that many of the Technicolor routers have been rather odd, generating thousands of DHCPv6 requests per second. We have remotely rebooted many of these, but some still remain. We will be taking steps later today (Sunday) to shut down IPv6 on the affected routers and advise customers that the router needs power cycling / rebooting. Sorry for any inconvenience, and we are at a loss as to why they are behaving like this.
We have managed to sort the problem routers for now (mostly by rebooting) - if you don't have IPv6 working properly on a Technicolor - please turn it off and back on again.