NOTE: This affects both HS100 and KP105, but I have seen it mostly on HS100

I have been using Kasa smart plugs since 2019 and have generally found them to be quite reliable. However over the last month I have had three separate instances on three different plugs where each plug dropped its WiFi connection and refused to reconnect. There didn't seem to be any reason for this (power cut etc). The plug just randomly decided to disconnect. No other plugs were affected at the same time (I have five in total).

Switching the plug off at the wall socket and immediately on again did not restore the connection (red status LED).

However, in each case, if I switched the plug off and left it overnight, when I powered it back on the following day it immediately reconnected. I found this on the first plug by accident ("one last try before I throw it away") and it has also worked on both subsequent failures. The worrying thing is that this is becoming a regular occurrence and it is getting to the point that I no longer trust my smart plugs to be reliable enough while I am away from home.

One might point the finger at my router as the common denominator, but I have numerous other IOT devices connected and none of those have been misbehaving recently.

Has anything changed at the KASA back end which might be causing this?