Ya my router has to do tagged PPPoE through the ONT even though I pay for a static /28. At least I don't have to also do RIP for the subnet like Xfinity requires.

Interestingly, if I pay for their IPTV service the internet side becomes a bare ethernet port over which I can do DHCP for the upstream interface and number the downstream subnet out of my /28.

I have debated paying for TV service as a sanity fee.