To avoid an IOT device to disconnect and connect itself from 2.4 GHz many times a day, sometimes multiple times per hour I further narrowed down the 2.4 GHz Professional settings to below, the last I did was set "Enable WMM APSD" to Disable, a few other options I already set to Disable for other disconnect issues.
The 2.4 GHz wireless now seems to be stable, with only the expected disconnects and connects from devices that are really leaving or been shutdown and returning or be powered up.
The 2.4 GHz wireless now seems to be stable, with only the expected disconnects and connects from devices that are really leaving or been shutdown and returning or be powered up.