We will upgrade RabbitMQ and Erlang versions on the shared server "white-mynah-bird". We will also adjust the underlying hardware to more modern. This requires all queues you want to keep messages in to have a HA-policy with automatic queue syncing.
For minimal disturbance, remember to always configure your clients to automatically reconnect on connection loss. Please do a full reload (cmd-shift-r) if the management interface is not accessible after the upgrade has been completed.
If you can't allow any scheduled downtime we recommend you to move to a new dedicated cluster via queue federation, as explained here: https://www.cloudamqp.com/blog/2015-07-08-migrate-between-plans-rabbitmq-queue-federation.html