Hi Rahul,
We now have the Draytek working with NDRA thanks to your superb help.
However, we do have 1 issue that is maybe working as it should or, is not.
The actual end node (laptop) seems to be keeping its IPv6 address from previous configurations. In other words, I configure the RADIUS for IANA using /128 and a PD of /56. The CPE gets the correct address and delegates /64 prefixs on the LAN. The laptop on the LAN gets an IPv6 address and that's fine.
I then connect an NDRA CPE and reconfigure the RADIUS with a /64 and a /56 for PD and change the addressing to test. Now I find the laptop has the old address AND the new address assigned to the interface. The IPv6 testing still works, but here is the question:
Why are all the addresses staying on the laptop?