TL;DR - We use Phonegap/Cordova plugin for push notification handling.
We have own package for UPS registration (part where ID needs to be send to UPS server.
It will work with Ionic and Cordova.
Docs may need some refinement.

Summers Pittman I might not understand what you meant but I think "JS SDK wasn't going to get support for UPS" is not fully true. Let's collab on this to avoid confusion.