There were a bunch of notification icons at the top-left of screen. I tapped on the Dismiss icon (3 staggered dots) at the top right, and the notifications vanished. Was wondering how to bring them back. Reboot does not do it. Perhaps, as you state, notifications are a one-time thing. Thanks!
Addendum: Just received a notification (new updates) as I was typing this, so I guess all is OK.