Delta Process Overview

The delta follows this process:

• 5 pm EST on second Friday of the delta month: Code freeze goes into effect. No changes to production can be made without management approval between now and when the delta is run
  
• Monday prior to the delta: Delta dry run is performed against the Client Test environment
  
• Monday through Thursday: Delta testing is performed within the Client Test environment
  
• Friday prior to delta: Decision is made on whether or not to perform the delta
  
• 5 am EST on third Sunday of delta month: Delta is performed
  

The delta begins at 5 am EST to ensure that the impact on clients is as minimal as possible. The process time fluctuates based on the size of the delta and the number of changes being implemented. During the delta, the system is locked down and cannot be accessed. When the delta is complete, a notification is sent to clients on the DDI Delta list and the system is once more accessible. After the delta, DDI staff perform limited testing to ensure that no critical systems were negatively impacted during the delta process.