User tags are now propagated in alarms and messages sent by both the hub and the controller (version 7.70).
Previously, both the hub and controller read user tags os_user1 and os_user2 from robot.cfg.
Now, the hub reads user tags from hub.cfg. User tags have been added to the hub’s General Configuration section in Admin Console, which set os_user1 and os_user2 in hub.cfg.
Therefore, if the robot is also a hub, then you would need to set the user_tag at the hub level.
If the robot is not also a hub, then you can set the user_tag at the robot level.