Move Existing Vault Stores onto new Storage

We have Enterprise Vault 10.0.4 and currently archive MS Exchange 2010/2013 Mailboxes and Clustered MS File servers (windows 2003).

My question is how would I go about migrating my existing vault stores and partitions from the current file servers to our brand new Hitachi Content Platform Storage system?

I'm assuming downtime would be required whilst the copying of partitions took place.