Luckily I had guarantee still on and got new decos. They have firmware 1.5.3 and works like charm. I will stick on that firmware. Need to wait until stability problems have been solved. Of course can...

@David-TP Do you have any solution for this problem? With latest beta 1.6.0 Build 20220816 Rel. 31542 all 3 Decos are loosing connectivity several times per day. I have my set in access point mode....

@David-TP I installed this latest beta earlier today but already once wifi connection dropped. Needed to restart main Deco. Interesting, that this root cause hasn't been found or has it?

@David-TP Thanks for your reply. Here is my topology. It has been little bit better, when switched off "Smart DHCP" like others have been reported here as well. So Mesh is via Ethernet. There has not...

@TP-Link After updating M5 firmware to 1.6.0, main Deco looses LAN connection every day once, which didn't happen with earlier firmware 1.5.3. Would be nice to get updates without loosing stability....