@NuklearNik 

Hi! I have Deco X55 US/V1.6 network and I configured it exactly as I preferred and it is amazing...then the 1.4.1 firmware update was released.
 

All I can say about this firmware is at first it was a complete nightmare. I was almost to the point I'm at with my 3 Deco X55 US/V1.26 throwing them against my brick house (they've not been used in a long time because there's never any firmware updates, more on that). 

I researched everything I could but nothing. Then I thought why not try just doing a factory reset, setup a new network and see if by chance it may work.
 

I always unplug anything I can which uses WiFi when I'm doing a firmware update. I didn't the first two times and it seemed as if devices weren't functioning as great as they did so when the next firmware update was released that's when I started unplugging everything I could, just not my thermostat, doorbell or whole house generator. I absolutely noticed a difference. 

When I began the process of the factory reset the first thing I did was unplug everything (from the outlet as well as for example a fire tv stick, I removed it from the tv). I then did the factory reset, created a new network after testing it with my iPhone and iPads and seeing I easily connected, I then (yes it definitely takes time but imo, I think it's worth it) went through my house and started with one room connecting any devices that used WiFi then connected each to my new network. After everything was back online it definitely worked so much better. Every so often either my Nest thermostat or Ring Doorbell would drop connection but immediately reconnect. Everything else I was experiencing which were almost exactly the same and it seems to be common from what I've read, didn't happen after creating a new network. That's how I fixed the 1.4.1 update for my network.

I check for firmware updates (mine even though it's enabled will not automatically update, I check twice a week). I happened to see finally they'd released a firmware update for my 3 Deco X55 US/V1.26 and was psyched because I thought I can begin using them again and just maybe all my Decos will have the same features (I thought I researched for such a long time and was ready to buy my Decos but what I missed was there are different versions and builds and I can't stand it). 

I used the same method as described above, did the firmware update and what a complete horrible, terrible mess. It actually took three tries to finally get the firmware update. I kept receiving error messages. Nothing would stay online, it would show the Decos were offline when they had green lights, if I tried to reboot I received an error message every single time, when I decided to try to reboot on one occasion, went to the page it only showed the main Deco and one additional, 2 out of 6. They stayed online two days and I was done. I was just getting ready to throw them in the trash and I thought of something I'm going to try. I'm going to try putting the firmware (1.4.1) on the V1.26. I figured since I'm going to trash them, if it doesn't work or becomes a brick it's not a problem because they're going in the trash anyway. I guess I'll see in a little while because I hope to try to figure out how to do it and try it later.

Good luck to you and anyone who was the winner for the 1.4.1 firmware update. What a mess it was at first.
 

I will add I absolutely love TP-Link products and never purchase any other brand. I've never had any issues whatsoever until the 1.4.1 firmware update then the firmware update for my 1.26 version. I really wish I'd known about the chance of getting different versions because I would've gone a different route when I purchased them.

Have a great day and always be kind!