Once the Data Retention Policy indicates that a schools data is no longer able to be stored on our servers, we start by deleting from our databases the sensitive records. This action then renders any remaining non sensitive data into an orphaned state which becomes unusable. We have a cleanup tasks that then systematically deletes this data.
2 hours later, these records are then removed from our second data centre automatically. The data still exists in back ups at this point however they are overwritten a week later and at that point no longer exist on our servers.