@MeadowCreek,

The Signal Source Selection requires an update to either the 1.6 or 1.7 firmware. I believe that we are past the beta firmware stage( which was only for initial tests) so your best bet is to wait for the official firmware release for your model. You can keep an eye on the patch notes for your firmware updates as this feature should be specifically mentioned.

The goal of the feature is to add the feature to as many models as possible - however, there are no guarantees that every model will receive the feature. It is also worth mentioning that specifically, the signal source feature will not appear unless all Decos on your network are compatible with the feature, as all all the nodes need to work together to redirect or deny connections/requests.

For now, there is no way to force this connection unless you move nodes around so that the third cannot see the main node's connection and will be forced to use the second node in a daisy chain. It is worth mentioning that the Decos will reconfigure their backhaul routers when the node is rebooted, so you may be able to test different locations this way