Thanks! I’ll give that a shot. I didn’t do much troubleshooting because other devices could access those sites just fine using 9.9.9.9, so I figured it was something weird in Apple’s system.

I’ve never been able to chase it down, but Apple devices on my network always seem to have issues accessing some sites when using quad 9 for DNS. No problems with cloudflare, though. 🤷‍♂️

Can confirm. My router log showed that a neighbor’s iot device was repeatedly trying to connect to my WiFi every 10 seconds or so. It was by far the most dominant event in the log.

The only way to stop it was to block its MAC address.