With Project Server 2013 and Project Online, Microsoft replaced the server-side scheduling engine with the Project Calculation Service (PCS), bringing the power of the Project Professional scheduling engine to the browser. This new service also powered a new cloud-ready Project API, also known as the Client Side Object Model (CSOM).

What’s changing?

There will be changes in the following three areas:

  • Project Detail Pages (PDPs) that today rely on the legacy server-side scheduling engine to process and save data will now use PCS exclusively.
  • The Project class of the PSI is being removed. Customizations leveraging methods in this class will need to be updated to instead use Project CSOM methods.
  • As Microsoft identifies gaps between scheduling PSI and CSOM coverage they will invest in new CSOM methods to unblock these scenarios. These improvements will roll out online when ready and ship to Project Server 2016 customers through Public Updates.
What’s the timing?

For on-premises customers, Project Server 2016 will ship with all of these changes implemented. As previously mentioned, CSOM improvements will ship with Project Server Public Updates.

Online customers will see some of these changes rolling out within the next month. They will roll out these changes in phases and continue to work on CSOM improvements for the foreseeable future.

For all your Project needs, please contact us. Here is the entire article from the Microsoft blog.