Upon investigating, it appears that the issues Discord are having at the moment have resulted in the gateway connections for Fire's clusters getting stuck in a form of limbo state where it appears to be connected but nothing is being received (and I have no way to test if anything can be sent as I'd normally do that via a command)
I will attempt to restart clusters, starting with the cluster that has the least unavailable servers (cluster 3 with only a single unavailable server), since servers being unavailable on connect can slow down startup and might result in further issues