Ok, I can report issue resolved and share experiences now. Flowroute support responded by email to me later in the morning indicating a 65 minute outage affecting outbound calls. Stated cause : "A third-party Location Routing Number (LRN) provider had a widespread service outage." (Maybe someone more expert in this field already knows what vendor had that problem earlier today). They reportedly had to engineer around this provider to restore service and are investigating with 3p vendor to ensure this issue does not re-occur.
All said, I'm pretty impressed with Flowroute. I've had them on 4 lines for about 5 years and can honestly only remember 2 short outages. When they have occurred they are very open to their customers about the root cause/remediation plans. And you can't beat their price compared to the big traditional "establishment" vendors. Hopefully this was useful for someone else