Resolved: Scheduled maintenance for Yammer on Saturday, March 30, 2013

On Saturday, March 30 from 1:00 PM to 4:00 PM EST, Yammer will be performing a major database upgrade which will require approximately 3 hours of downtime. All precautions have been taken to ensure downtime will be as minimal as possible and no customer data will be lost.

More information: Resolved: Scheduled maintenance for Yammer on Saturday, March 30, 2013

Story added 1. April 2013, content source with full text you can find at link above.