Are you sure you're looking in the right spot? My firetv auto-updated, but the option is still available.
1.From the main (Launcher) screen of Amazon Fire TV, select Settings.
2.Select System > Developer Options.
3.Select ADB Debugging.
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? | Terms of Service