Ads Evading Pi-hole with iOS 27

I YOLO installed the iOS 27 beta and noticed ads creeping back into apps that have been clean for years. The Pi-hole was still running and still showing blocked queries — the ads were just loading anyway.

The culprit was “Connectivity Assist” in the Wi-Fi settings, aka Cellular Fallback. When the Pi-hole blackholes an ad domain the request fails, iOS decides the Wi-Fi must be flaky, and helpfully retries the same request over mobile data — where there’s no Pi-hole in the path. So the ad not only loads, it burns through my data allowance to do it.

Flipped the switch off and ads are properly being blocked again.