The template used to upload or update user approvers/controller can be found in the "admin settings" - "users", and click on "+ add" - "Assign approvers/controllers" or can be found here for assigning approvers and here for assigning controllers.
The file consists out of three columns:
In this column the email address of the approver or controller can be added
In this column the email address of the user for which an approver or controller needs to be assigned can be added
This column can be used to establish or brake the link between the user and his/her approver/controller.
When the relationship needs to be activated: active = 1
When the relationship needs to be de-activated: active = 0