It is a TL-WA855RE. I did a live chat and the tech asked me to move the extender to another outlet and I did that. To my surprise and delight, the phones do not seem to be affected by this new...

I plugged in my new range extender, did nothing else, and all 3 AT&T cordless phones showed "No Line"! Unplugged range extender and, again, had dial tone. Phones are hard wired to charging dock but...