@IgorN77 @TP-Link_Deco Please comment.

Well, the whole discussion seems to be centered on disabling the DHCP server feature in AP mode, whereas an alternative solution (making the design less sensitive to external (modem-induced) network...

@TP-Link_Deco Dear TP-Link team, as I am suffering from exactly the same problem (rogue DHCP issues with multiple wired Deco units and Zyxel modem), I would like to suggest another idea that may be...