Hi @uncvrd, to provide an update here: it turns out that one of the major backbone networks started to (incorrectly) route some of our traffic from the US to APAC. We applied a workaround to this by stopping to advertise our IPs to that problematic network. As of now, it seems that most US traffic is routed correctly, but we have no great visibility into ATT’s network.
If you are still seeing this issue, a traceroute6 from your side would still help a lot. In addition to the IP of your fly.dev domain, could you please also try tracerouting to the following IPs: 2a09:8280:e632:: and 2a09:8280:e621:: – these are (respectively) IPs in the sin and lax region, and although they won’t respond to pings, hops in the middle as shown by traceroute will help us understand why you are being routed to sin.