How are mobile HA notifcations routed, where do they travel?

I’ve assumed that when sending a notification to the Home Assistant mobile app, the notification goes directly from my HA host to my mobile device, traversing only the internet plumbing in between. If true, then when I’m home, the notification wouldn’t leave my home network.

But, when I see log entries like:

mobile_app push notification rate limits for your iPhone: 5 sent, 300 allowed, 0 errors, resets in 20:42:22

…it makes me wonder: why the 300 limit?

So, is the routing direct…or do notifications transit through Home Assistant’s infrastructure, or…?
Obviously, I’ve never tried to trace route it.


It uses Firebase Cloud Messaging.

Oh snap, Firebase!?! That’s a google product, right?