We have begun a two-part implementation of the integration with Mimecast, and you can now send Mimecast event logs to Blumira for logging and reporting. At this time, detections and findings will not be generated, but you can review log data in Blumira's Report Builder.
Mimecast detections and findings will be available soon in the next release for this implementation. We recommend configuring your integration as soon as possible to begin receiving notifications as soon as the capability is released.
Reference: See Integrating with Mimecast for more information.