Who? The infrastructure team that did the move didn't even tell anyone. They were decommissioning old servers, and moving the VMs to new hardware. I'm just a lowly developer that had to troubleshoot why SMSes stopped going out.
Observability and alerting is pretty standard devops. Both the dev and infrastructure teams dropped the ball here. But at least as part of remediating this you added alerting to make sure you’d notice when your twillio connection fails in the future, right?