I’m going off what I’ve been advised when asking elsewhere about this issue. Admittedly, I’m quite a novice to iOS dev, I’m more attuned to JavaScript. So basically, if I have my app open, or recently opened, and I trigger the Health event, my app will successfully send a notification. However, if the app has been force-closed, or hasn’t been opened recently, the system will queue up the notification until I next open the app, at which point all queued notifications will come through.