Confluence cannot be scaled up/down beyond original cluster size on Azure

Issue Summary

Once Confluence has been installed via the Azure ARM templates it cannot be successfully scaled up to n+1 nodes.

Steps to Reproduce

1. Provision a Confluence cluster via the ARM templates/Marketplace. Confirm parity between the node count reported via the VMSS and the Confluence clustering UI..
VMSS instances

Nodes reported via Confluence clustering UI

2. Scale the cluster up by 1 node via the Azure console

Expected Results

Cluster should scale and new node visible in console

Actual Results

At this stage a new node will be provisioned by the VMSS and this will be visible via the Azure console. However on looking at the Confluence clustering UI we see that the new node is not available:

Workaround

Scaling up n+1 nodes from the original cluster size for Confluence on Azure is not possible.
You will need to ensure that the cluster size you select when deploying will be capable of serving all of their expected volume/load.