As an afterthought, I am confirming that we are using the RT-AC87U, 10 years old, showing it updated to 3.0.0.4.382_52545-ga0245cc on 6/11/24, with log entries that jump from May 4 (yes, Star Wars day) to present day when "WAN was restored". Maybe with enough of us collecting information...
I just joined SNB just because of this thread. I've been tearing my hair out for weeks on this problem, that, due to poor search results, I thought was unique to my network!
I thought at first it was related to my ISP, COX, who sold/gave its email system to Yahoo to manage at this same time...