When reviewing the Revision History for an item the date in the Description doesn't match the Creation Date. For example, an item's Schedule State moved from Accepted to Completed. In the Revision History it shows the date removed, but its different than the Creation Date when the item's Schedule State was changed.
Release : SAAS
The Date in the Revision History description is the date that was recorded originally. So in the example above where the Accepted Date was removed that Accepted Date was the Date recoded when the item had been Accepted originally.