The pings are there to check that the connection is still active and is not needed to send a notification. If I can maintain an active websocket to my home server for 30 mins on average, decreasing the ping frequency would help with battery life without delaying notifications.
maintain is one thing its another to take 30 min to realize it needs to reconnect, thats where teh delays come.
You could also send the ping before the notification.
before what notification? the app has no idea there is one. The app sends teh ping not the server.