I don’t know if this is an iOS 27 thing or it’s always been like this: when you’re on a wifi network that doesn’t support IPv6, IPv6-only destinations route over mobile data (
if it supports IPv6 and you have Connectivity Assist turned on, which is the default.

Maybe IPv6-only destinations are rare enough that this isn’t a big problem, but it’s kind of shitty to split routing like this. #ipv6