My Deco Mesh consists of an X20 (Main, Router mode), (1) remote W3600 (aka X20), and (3) S4. 

X20, W3600, S4 are connected via backhaul over a TP-link switch (TL-SG1008D)... this all works fine. 

One port of the TP-link SWITCH connects (via Cat5) to my Dell 2716 16-port switch, and all devices on that switch are working fine. 

I have a TP-link Archer A7(C7) AC1750 Wi-Fi router connected to the Dell switch that currently ONLY exists for its USB Network Attached storage feature... the A7 is in AP mode, with both radios turned Off... no Wifi active.   This currently works... it's just acting like a dumb NAS... with 3 open Gbit ports. 

Here's the question... 

I'd like to use the 4-port Switch in the A7 for the Deco backhaul, as I need to move the TP-link switch to a different place on the LAN, to be used as a wired Deco backhaul wired extension. 

Does anyone know if the 4-port Gbit network switch in the Archer (AC1750) A7 is fully compatible with the Deco backhaul, and if this revised configuration would be compatible?

All backhaul connections would be sourced from my Main X20 Deco, which would be connected to the A7 switch, all other backhaul connections would also be through the A7 switch.   That (A7) switch would then also feed my Dell 16-port switch for Ethernet clients only. 

Quite the complicated mess, huh?