On 06-12-2020 there was an issue with our backup server's script, which meant that the node was unavailable for 48 minutes (from 18:18-19:06 UTC).
The backup node was running at the time because the main node's Internet connection is unstable at the moment, waiting for it to be fixed.
The backup script has been updated, and should be performing checks every 2 minutes to make sure the node is running (this has been tested and confirmed to be working as intended).