They were supposed to improve student performance in the lowest-performing schools. But after several years of operating separately  those schools are going back in the Detroit school system.
4 years of results of the Education Achievement Authority have been less than stellar:

poor student performance, falling enrollment, mis-management and corruption.

Now the 14 schools under the EAA can return to Detroit Public Schools Community District, per legislation approved in Lansing in June.
Many details are unclear, like jobs.

And, will the 3 charter schools under EAA revert to the district?

The action is the first step taken toward the district goal of reversing years of falling enrollment.