I've had a pack of 3 Deco P9 devices that link to my Viriginmedia router (recently upgraded to Hub 5) 

Connectivity hasn't really been too much of an issue, but I have noticed as recently as mid December that the devices bandwidth has dropped despite nothing changing.

My first port of call was the ISP, but I've managed to get optimum bandwidth each time from the router to the outside world. The problem has been narrowed down to the Mesh network.

I have an outstanding support case pending, but the only other time that I needed assistance from TP LINK was when I tried to upgrade the firmware for all Deco devices. At that point, I had an engineer looking to connect to my computer in an attempt to work out what went wrong, I wasn't clear on what the root cause analysis was, but the service was normal. It just so happens that after the issues I experienced recently, I went to complete a firmware update. Hoping this hasn't caused anything to break/

Has anyone else come across the firmware update process to be problematic? Given that this was a premium purchase for me, I would expect this to be working without minimal fuss. Seems from what I've read so far these problems extend to more product families.