I am looking for a way to automatically assign all tasks associated with a service request to a technician AFTER the request has been approved.

work flow:

Template has assigned tasks that "activate after approved

Service request created

Assigned to tech that manages the approval process

After approvals service request reassigned to an engineer that will work the issue/problem.  At this point all the associated tasks need to be assigned to the engineer.  Before this point they should not be assigned

Is there any way to accomplish this.