VoIP pushes stop being delivered to the app if app killed with iOS 13

There’s been a longstanding issue with VoIP pushes not being delivered to the app if the app has been terminated and the device rebooted: PushKit notification not arriving after application kill AND device reboot

However with iOS 13 I’m seeing that they are not being delivered if the app is terminated without the phone being rebooted (currently observing this on 13.1.3).

This is 100% reproducible, but the number of pushes that get delivered to the app after it’s terminated for the first time appears to be variable. Often the app will continue to receive pushes after being terminated but only a few before it stops receiving them entirely. However, on some occasions it doesn’t receive any whatsoever after being terminated.
If the app is launched again then it starts receiving them again BUT only if the app is in the foreground – move it to the background and it doesn’t receive any.

I’m going to file a radar for this, but before doing so has anybody else observed anything similar?

Source: Ios