UPDATE !! [RESOLVED]
The issue has since been resolved.
There were network latencies that resulted in endpoints on both Safaricom side and our side timing out and the requests dropping off.
We are currently monitoring performance to ensure this is fully resolved.
You may experience degraded performance on Outgoing and Incoming messages on Safaricom network.
The issue has been escalated to Safaricom engineers to check both their applications and network so as to resolve the issue.
We'll share progress as we receive.