I am experiencing issues with setting up my TP-Link Deco X75 Pro mesh network where the main router is on a different subnet than the other Deco nodes. Despite attempting various configurations, the satellite nodes are unable to connect to the main router.

The main router (Deco) is intended to be on a different subnet than the satellite nodes.

When I set the Deco system to Router mode, the satellite nodes consistently fail to connect to the main router. The LED indicators on the satellite nodes remain red, indicating a connectivity issue.

I then switched the Deco system to Access Point (AP) mode, but the satellite nodes still could not establish a connection with the main router. The LED indicators continued to show red.

My intention is to have the main Deco router on one subnet and the satellite nodes on another subnet, yet maintain a functioning mesh network.

In Router mode, the satellite nodes could not connect to the main router, indicated by red LED lights.

In Access Point mode, the issue persisted with the satellite nodes still unable to connect, showing red LED lights.

Main router IP address range: (Example: 192.168.3.x/24)

Satellite nodes attempted IP address range: (Example: 192.168.4.x/24)

I have restarted all devices including the main router and Deco nodes multiple times.

Firmware on all Deco devices is up-to-date.

No IP conflicts detected.

I can confirm that on the same networks the set works in AP mode and also router mode.

Any ideas if that is possible at all? There is no visibility so I have no idea what is going in under the hood to troubleshoot