sfx2000
Part of the Furniture
I'd love to check how well (or whether) IPv6 functions. But there is no equivalent of the standard DHCP WAN configuration all routers support for IPv4 that is consistently supported for IPv6.
Having an IPv6 DHCP WAN type is necessary but not sufficient. How the LAN handles addressing is just as important and that's where things get messy...
I'm sure you've reached out to the suppliers - both for the test equipment and Vendors/OEM's on feedback - but as you state, it's the WAN connectivity that is problematic... but if one were to stand up a small DCHP6-PD "WAN" server, this might help - at least to get a baseline performance, as this is fairly common (it's the options that are tough across different operators, Comcast and Cox have both had issues here - Cox's is ongoing even now, as they pretty much rolled out v6 in the last couple of months)