OK, thanks for the details.

I've recently setup TP-Link Deco M5 with 3 units. One is the primary/main unit and connected directly to my modem, and the other two are connected via Ethernet backhaul. So, in ASCII art diagram...

I've called support and requested this information as well. I've wired all of my Decos and would like confirmation in the mobile app that each unit is indeed routing via Ethernet backhaul instead of...