With the new Sked mobile app and Notifications update arriving, users need to set their notification preferences to get push alerts.
Head to your Group Settings
Enable Notifications for the group(s) you want to subscribe to:
Post Notifications for manual publishing alerts are automatically configured as on for Mobile by default, and you can configure additional channels and settings from the preferences pane.
Note that preferences shown are your own user preferences, each users will only see their own preferences on this screen.
Email alerts will continue to be delivered, and will be migrated to the new system in the near future.