Will this latest firmware resolve IPv6 not working on a fibre connection?
If you've got an IPv6 address and the HG659 then you should be fine running IPv6 traffic, see this thread for more detail. From what I can see on the network you're connected OK, and an IPv6 ping from your router works fine. Give the router a reboot first to rule that out, then call our tech support and get them to investigate. If you have no luck with that, PM me.
To upgrade it's in the Maintain menu under Device Management. I think you need to be logged in as Admin to do that.