@AlphaB not sure if this will help, but, have a look at the following post, specifically the pfsense settings:
And this thread as well, which was started by @JKnott :
Perhaps @JKnott can offer some advice.
I don't have any experience with Unifi USG, but it should have some settings comparable to other devices mentioned in the link from Datalink. Start with the basics and see what's happening without that Sophos device. Does the USG have a WAN IPv6? LAN? Do other devices on the network get an IPv6 address? Once things are working properly you can then worry about that Sophos device.
Incidentally, that WAN address is not used for routing. It's just a /128 address that's used to provide a WAN address for the router and nothing more. IPv6 generally uses the link local address for routing.
Thanks and yes I had seen those links a while ago and they helped in the setup of the Unifi USG. The Sophos seems to be speaking a different language: it seems to be hit or miss and I even tried forcing the address but it refuses stubbornly!
I do wish to persist will keep my eyes peeled for any users who have had luck on this one.
Thanks @Datalink for the links and will help to perhaps finally have one resource for future reference as well.
I just looked up that Sophos and it's also a firewall. Are you using both the USG and Sophos firewalls? If so, that's the problem. Rogers uses IPv6-PD to provide the LAN prefix. If you have another firewall/router after the USG, you have to manually configure everything, including one or more /64 prefixes from the /56 Rogers provideds.
Perhaps you could better describe what it is you're trying to do.
@AlphaB here's some food for thought. The Hitron modems, in Bridge mode provide 4 active, independent ports. Two of those ports will provide connected devices with independent IPV4 and IPV6 addresses. Beyond those two ports, the other ports are only supposed to provide IPV6 addresses only. So, in theory, with the Sophos and USG connected to their own ports on the modem, you can run two independent networks.
You should be able to connect both devices, then restart/reboot the modem so that each device is assigned an IPV4 and IPV6 address.
First off, IPv6 is not making your MAC or host name available. That is being done by your browser reading that info and providing it to the site. There is absolutely no other way for your MAC address to be revealed, unless it edits the MAC based IPv6 address to work out the MAC, and the only other possibility for the host name would be if it's registered on a publicly available DNS server and the site does a reverse lookup. Normally, something called a "privacy address" is used for outgoing connections, which would have no connection to the MAC address or host name. There's no reason to not enable IPv6. As I am not familiar with your hardware, I can't comment on enabling RAs. However, if you get an IPv6 address and are able to reach the Internet, it's working.