We had to create a new Workforce project which is almost a copy of an older one. However, in our older version, the assignments table had assignmenttype, workerid and dispacherid as esriFieldTypeInteger. Now in the new project, these fields are of type esriFieldTypeGUID.
Why is it different and how could we change it to esriFieldTypeInteger? We have an API built to work with the Workforce and changing of the field types creates an error.
We've made some major changes to the Workforce schema for this new release; they're outlined here:
The use of esriFieldTypeInteger for assignment types or workers and dispatchers is no longer supported.
In addition to what Craig said, if you need/want to create a Classic Project, you can using the ArcGIS API for Python and the create_project function.
import arcgis project2 = arcgis.apps.workforce.create_project('new_project', summary='This project was created by Python', major_version=1)