The IC itself was actually performing as expected and was not down, however one of the Boundary Nodes (in US-east) which acts as a gateway for the IC experienced intermittent issues that prevented failover. As such users in that geo-area who were DNS routed to that impacted boundary node experienced their requests being dropped by the BN.
Advanced users in the impacted area were technically able to reach the IC by talking to other boundary nodes. The method of targeting specific boundary nodes is a bit opaque, so we will be writing up simple steps on how to do this.
Preventing/mitigating issues like this one are why we are trying to get boundary nodes decentralized as soon as possible.