Did you have a static IP address set on your PC?
In over 20 years of working with IP and networking, I have never seen an OS or update change a static IP address.
DHCP is used for convenience and managing large networks. The IP address of your cable/DSL modem and WAN side of your router obtained from your ISP (for home networks) will almost always be DHCP assigned, although in some cases, a static IP address can be supplied for a fee.
However, on the LAN side, you can choose whether to have your router automatically assign IP addresses through DHCP or not. I prefer static IP addresses. They don't change, and if you need to troubleshoot connections through the use of the IP Ping command, you can be confident of the correct IP address.
DHCP can be useful to hand out addresses to visiting wireless laptops, and many router DHCP server programs can be used in a
Static DHCP mode, which can allow the DHCP to always assign the same IP address to designated computers or devices based on their MAC hardware addresses.
On the subject of Windows Automatic Updates, I suppose for those who know next to nothing about computers, that is probably the best way to insure that important updates are applied. But for everyone else with even just a bare minimum of computer savvy, I recommend to configure Windows Update to "Download updates, but let me choose whether to install them".
There was a Windows Update for my integrated Realtek Gigabit Network Adapter, that rendered my network adapter unable to connect (Of course, it didn't change the IP address because I was using a static IP address, and I was able to simple roll back the driver to the previous version). Inspecting the available updates before installing allows you to ignore updates like these, as well as superfluous ones like the 34 language packs, Help files for those that don't have a persistent Internet connection, etc. that you don't need.
You can also choose to hide (or restore) any selected uninstalled updates from view to simplify things.
Steve