Ubuntu 20.04 getting wrong IP address

Yesterday (early August 2021) my Ubuntu 20.04 installation started configuring all network interfaces (wifi, ethernet) with IPv4 addresses from the wrong network segment block, namely 192.168.0.x. IPv6 still worked fine.

I didn’t figure out whether that’s due to a change in the router or the OS (I suspect the router, because the situation improved when increasing the DHCP lease time [2]), this solution however [1] works for me.

The file

/etc/netplan/01-network-manager-all.yam

must be reconfigured, in my case

network:
    renderer: networkd
    version: 2
    ethernets:
        enp5s0:
            dhcp4: true
            dhcp-identifier: mac
        wlp6s0:
            dhcp4: true
            dhcp-identifier: mac

[1] networking – Wrong IP address from DHCP client on Ubuntu 18.04

https://superuser.com/questions/1338510/wrong-ip-address-from-dhcp-client-on-ubuntu-18-04

[2] What is a good DHCP lease time?
https://serverfault.com/questions/251815/what-is-a-good-dhcp-lease-timeout-configuration