For project-scope automatic actions, restarted updated tasks behave like newly added tasks. If the project-scope step has not yet been executed in the workflow, then the previously existing tasks that are still active wait for the restarted tasks to catch up when they reach the project-scope step.
However, if a project-scope step has already been executed in the project, the project-scope step is executed on only the new and changed tasks passing through the workflow again, and doesn't factor in existing tasks that have already passed the project-scope step. For example, if the project-scope automatic action Generate Translation Kit is being used in the workflow, the original kit still contains the old versions of the assets along with everything else, and the new kit that is generated by restarted and new tasks will contain just the changed and new assets.