OMG. Your experience on this makes my blood boil for you, Dave. And it feels like deja vu.
The customer service folks on the phone and chat are clueless on this issue, despite how recurrent it is. Plus these bureaucrasies RARELY acknowledge known defects. And that the chat person told you to get a new router even though it has nothing to do with that???!!!!! Outrageous.
Keep making noise. I think it is your (our) only recourse on this issue at this point.