WHAT YOU NEED TO KNOW
Microsoft has defined the dates whether Administrators can choose between activate or not the new Resource Engagements Features.
Below is a timeline, made in Microsoft Project, that illustrate the dates:
Global Administrators will soon be seeing an update message on Office 365 message center regarding Project Online’s Resource Engagement feature.
Microsoft has updated the FAQ document here: FAQ: Resource engagements are replacing the old resource plans
Below is how the feature activation alert look like: