Actually, I screwed up and had the unit plugged into a power strip. Although I had used the outlet with my AV2000 set, I didn't have it going through the power strip. My units are now connected via...

Has Telnet been enabled entirely in the commercial firmware?

@Plymuff_Neil Same here! Just installed the 3-pack. The app is showing one using a very, very weak Wi-Fi signal for backhaul instead of powerline. And I had previous TP-Link AV2000 powerline adapters...