@NiekT The problem I've found is that any seemingly-stable set-up using affected devices will eventually fail due to things like power cuts, brief internal service outages or just the actual DHCP...

Can confirm the same problem with the TL-WPA4220 v4.0. Had been installed at a client site with no problems for a few months and after a power cut, the Wi-Fi extender is giving out DHCP leases,...