@TP-Link 

Well.... Agree to Disagree....  I guess you are probably referring to what is "expected" or "supposed" to happen but realistically, that is not the case. I did a test with three X68 and there was absolutely no way for them to daisy chain. Look at the diagram I added in a previous post. My devices were pretty much in a straight line diagonally from floor to floor and, still, the basement one was connecting to the third floor one entirely bypassing the second floor Deco device.

Again, I believe more testing needs to be done, a manual source selection should be added to the firmware for customers to manually test different implementations and, most importantly, eliminate all options, but, most importantly, it needs to be clearly advertised because, in my case, it leads to wasting my time.

Also, I understand that the engineers may be doing everything they can but the support turnaround is not effective which is the primary reason why I decided to return all the units.

I'm more than willing to be a "test case" for this, just send me three units and we'll go back and forth with every scenario. Willing to even open terminal access to each of the devices for the engineer to configure directly.

I guarantee you, once this feature is added/corrected in the X68s or even X90s firmware (as an option), I will get the devices again but, in the meantime, happy with my Google devices...

@TP-Link Hi, can you send me the beta firmware that allows daisy chain on Deco X5700? I sent you a couple of messages which never got replied. Thank you.

@TP-Link 

I have 3 Decos

1. M9 (main deco)

2. M9 (sub deco)

3. M5 (sub deco)

Would this work for the M5 (which is the deco I want to manually connect to my sub-deco (M9)?

@TP-Link I've installed the firmware from the first post in this thread on all 4 x of my Deco M9 v2. How do I now go about setting a manual source for the slave nodes?

I tried from the Deco app, the source signal isn't selectable. I also tried "Network Optimization" but it said my network is perfect.

Have I missed something?

Thanks!

@TP-Link No it hasn't made a difference. The unit on the 3rd floor still connects to the main unit on the first floor. It should connect to the 2nd unit directly below it on the second floor.

@TP-Link 

Will there be beta firmware for W3600 and W2400?

My W2400 keeps connecting the the furthest W3600 until I reboot it. Then it connects to the closer deco and my internet speed is great

Sorry, @TP-Link but you are incorrect.

As others have already pointed out and from my own testing.

The devices will _not_ connect in a daisy chain topology.
If the in a string like

A - B - C

if C is too far away from A in order to connect, it will under no circumstances connect to B. It simply can not find the network. 

This is not how the product is advertised.

I hope there is an update in the works to enable this functionality as without it, these devices are not very useful.