iTunes 12.13.4.4 x64 not recognizing any iOS update after 17.1.1

On a Windows Surface Pro 9, x64; Win11 Pro 23H2 with all current updates installed. iTunes version 12.13.4.4. Phone is an iPhone 14 running 17.7.1 and I've been getting a lot of notifications about updating to the current iOS of 18.3.

I have been attempting to do this through iTunes to no avail. I prefer to do a computer based update rather than OTA. I was able to backup the phone without issue to the computer. I keep getting an error on iTunes that the current iOS 17.7.1 is the most to date when I hit the Check for Update button after performing a backup/sync to the computer. Tried several different cables, none of which are through a USB hub. Same message from all.

On the Surface 9, which is my primary personal computer, and thinking it was an issue with iTunes, I performed a diagnostic through the help menu and it passed with flying colors. I uninstalled iTunes, rebooted, reinstalled iTunes through the Microsoft Store and received the same message. Uninstalled iTunes again, rebooted, reinstalled through the direct download from the Apple Servers. Same message.

Tried on two additional computers, first a Surface Pro 6 running Win 10 x64 and iTunes 12.13.4.4. Second, a HP XPS 13, Win 10 x64 and iTunes 12.13.4.4. Received the same message that the current iOS is the only one available on both computers.

Home internet has both Wi-Fi and hard line connection options to the DSL modem. Tried both connections with all computers without success. Speed tests give 20Mbps down/ 3Mbps up with under 13ms ping. Have not had any issues with large downloads from the Apple servers in the past.

Any other thoughts / suggestions for a computer based upgrade?