@Matsla I see :) Do you use Homekit or something equivalent to control the Ikea hub or do you use the IKEA Home app straight up? I use Homekit with an Apple TV as a hub (through which I can control the Ikea hub) and this always works when I'm away from home. So when the problem arises and I'm connected to "the wrong" M9 satellite my solution thus far has been to disconnect from the wifi entirely and using Homekit via 4g - and that works. But it shouldn't have to be that way...

@Buffel2k2 

Hi

I'm using the Apple Home app for remote controlling my Ikea stuff, as well as the Ikea app. I'm getting the same behaviour from both apps, when connected to the mail Deco the remote controlling does not work (For some reason it works when I'm connected to either of the sattelites)

I am no longer able to controll my equipment when I'm away from the house (or on 4G)

@Matsla The behavior you're describing in which it only works when connected to the satellites seems to be exactly what's happening in my case. Except I'm able to control the lights while remotely connected. 
 

What's strange in my case is that the Philips Hue bridge (that's also connected to a satellite) works like a charm all the time, regardless which Deco I'm connected to... Is it because the IKEA hub and the Hue bridge has different ways in how they expose themselves/communicates in the network? It would be really helpful if a TP-link engineer could address the issue...