If I unlock my Verizon HTC one's bootloader and turn S-ON to S-OFF will I get an automatic notice to install 4.4.2?
Since this question hasn't been answered, no you won't. S-ON isn't what is keeping the phone from being a GE phone, it's an entirely different device model. You could at that point, however, install custom recoveries and ROMs that are based on 4.4.2.
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer?