I have an electric network that I received from one of our clients. It appears that the customer points are enabled and a part of the network. However, when I put a junction flag on one of the poles and try to trace upstream, it does not select any of the customer points. The secondary lines connecting the main 3 phase line to the customer is also a part of the network so I'm not sure why it's not selecting those? I hope it should be selecting them. I will attach a screen shot. I'm using 10.1.
Since you are tracing upstream I think you are not going to get those secondary lines... probably just to the nearest junction or transformer upstream. You can place some barriers up and downstream of where you put your flag then trace downstream and you will get those. Also make sure you have the secondary and customer points set as selectable.