AC56U / PPPoe, VPI/VCI

Hi, I am using a AC56U connected to a TP LINK 8817 in Bridge mode (so I can use DDNS/VPN). The issue is the AC56U does not seem to support PPPoA (witch makes is useless in the UK with a bridged modem). It also does not seem to enable me to input VPI/VCI, which potentially makes it doubly useless.

Or have I missed something.

I was getting the error "'The wireless router currently uses a private WAN IP address (192.168.x.x, 10,x,x,x, or 172.16.x.x). This router may be in the multiple-NAT...

AC56U / PPPoe, VPI/VCI