I started off thinking I have a random rebooting issue with my Hub One, but I have now been able to link it to an action on my home network. I run a server at home with a few VMs, one of which is my web server that also serves DNS for a few domains I own. This appears to be the one that will cause a reboot of my Hub One if I restart the DNS servers (or reboot the VM).
I'm not too sure where to start troubleshooting this issue as I can only guess that maybe there is a packet flood occuring when I restart the (BIND) DNS service. It appears to happen every time I restart the DNS service, but I cannot see anything in the router logs to indicate why.
Plusnet Hub One reports Software version 18.104.22.168.83.8.263 and Last updated 10/03/19.
It's not a major issue, but certainly something I would like to resolve as it is hugely annoying, especially when I forget and just restart the service.