@Kaneco One more thing: check DHCP Lease Time value in your Router. If it is set to more than 1 hour, or to forever - change it to 1 hour.

@Kaneco Thanks for sharing screenshot. Your Satellite Deco do use Ethernet backhaul and also total number of clients is not very high, if it is reasonably evenly distributed between Deco nodes. Also,...

@ih8win Sounds like X60 negotiated 100Mbps speed over Ethernet cable instead of gigabit, for whatever reason. To check that theory find device with gigabit Ethernet network card (desktop, laptop),...

@Kaneco With Deco running in AP mode IP addresses are managed by your Router TP-Link TL-R605. Check if it perhaps runs out of IP addresses. That could happen if you have many devices using randomized...

@luisalonsoramos It is most likely D-Link switches that are the problem. You can test that quite easily. Bring secondary P9 to where Main Deco is and connect them directly to each other: Internet ->...

@Dean069 You can power off Deco unit for as long as you need to. It will remember its settings.