From our service provider:
From 30/04/2018 10:28 UTC to 30/04/2018 16:23 UTC, US Toll Free and shortcode traffic failed, while delivery receipts were still indicating successful delivery.
While performing a connection migration with one of our US suppliers, live traffic was redirected to a test environment instead of the new production environment, due to a human error in the migration activity.
Internal tickets have been created to ensure the following corrective actions take place as a result:
Create a process for real-time communications with our provider during connection migrations.
Create additional monitoring during and after connection migrations impacting live traffic.
Improve our process for customer communications during incidents.