The Nubis team has just completed release v1.4.1. This is a patch release which is outside of our normal release cadence and is for a security regression.
Some time ago the Nubis account deployments were changed to enforce outbound proxies. MIG does not make use of the standard proxy environment variables. This regression caused MIG agents to stop reporting as they were blocked by the proxies.
The startup configuration for MIG was changed to specify proxy configuration as part of its boot time startup. After this patch release the MIG agents are once again able to traverse the proxies and report in.