Cannot connect to the Elasticsearch cluster

Our production Kibana cluster v6.5.4 at is down this morning :cry:
Error on the front page is:

Cannot connect to the Elasticsearch cluster
See the Kibana logs for details and try reloading the page.

The ES cluster itself look OK, thankfully. We have a 2nd cluster setup for monitoring, and it shows kibana health as red. When I first tried to drill into it I saw:

Monitoring Request Error
Service Unavailable: Check the Elasticsearch Monitoring cluster network connection or the load level of the nodes.
HTTP 503

Then, the third time I tried I see the system metrics and they all look fine, "System Load" etc are all low.

Is it possible to view the Kibana log in the EC clusters? Right now the option we see is to "Force Restart" but we wanted to check in here before going ahead with that!

Any help much appreciated!
Thank you,

Can you please open a support case at

Thanks Nathan,
We did open a support case and got an extremely quick reply!
Then, the cluster righted itself, without any input from anyone. We are still hoping to work out what went wrong.
Nothing interesting was visible in the Elasticsearch logs, from the console, and we don't see any way to view the kibana log for the Cloud clusters.

Thanks again for reading,