@SBK Yes. Connected to WeLink and working well!
It also came back to working well state after enabling IPV6 in Eero router to check that (07 Feb 0814 CST, which caused router reboot).
So, it seems like you have found a way to overcome whatever WeLink was doing differently than other ISPs (at least at this installation), or perhaps WeLink corrected something on their end (they did not tell me about any change, but they usually don't)
