Our app uses PTT framework and "Always" location tracking at the same time. By some reason, after backgrounding app, Dynamic Island shows only location tracking icon instead if PTT icon. And when user taps on it - application foregrounding instead of system PTT UI show. Only after first incoming PTT user can access system PTT UI.
Is it a bug or intended behaviour?
Sounds like a bug. My guess is that the two interface elements are "colliding" and the location UI is "winning". That is then reversed the any kind of PTT interaction forces the PTT UI active in the background. It's possible you might be able to avoid the issue by altering the order you activate things (activate location monitoring, then your PTT channel) but I'm not sure of that, as it depends on exactly how/when the underlying daemon's activate their UI.
In any case, if you haven't already, please file a bug on this then post the bug number back here so I can make sure it gets to the right place.
__
Kevin Elliott
DTS Engineer, CoreOS/Hardware