I just downloaded and tried the 2/21/19 version and I still do not get push notification. I uninstalled, cleared memory/cache and reinstalled. Still does not work. I get push notification from everything else, e.g., Gmail, updates, etc.
I even fiddled with the notification settings in the app and phone. It has failed on Honor 7X, Mate SE and Moto G5S Plus running Oreo.
I just downloaded and installed the March 4, 2019 version. Push notifications work on my Oreo phones! Hooray!