https://codesandbox.io/s/upbeat-frost-3tt25

1. Press Suspend, see "Loading..."
2. Wait five seconds, you'll see "Happy birthday" at some point 
3. You won't see it again no matter how long you wait

Expected: you'll see it every five seconds.
let [page, setPage] = React.useState('none');
        transitionToPage = setPage;
        if (page === 'none') {
          return null;
        }
        return (
          <Suspense fallback={<Text text="Loading..." />}>
            <AsyncText text={page} ms={5000} />
          </Suspense>
        );
      }
      ReactNoop.render(<App />);
      expect(Scheduler).toFlushAndYield([]);
      
      await ReactNoop.act(async () => {
        React.unstable_withSuspenseConfig(
          () => transitionToPage('A'),
          SUSPENSE_CONFIG,
        );
        expect(Scheduler).toFlushAndYield(['Suspend! [A]', 'Loading...']);
        
        Scheduler.unstable_advanceTime(400);
        await advanceTimers(400);
        expect(ReactNoop.getChildren()).toEqual([span('Loading...')]);
      });
      
      Scheduler.unstable_advanceTime(5000);
      await advanceTimers(5000);
      expect(Scheduler).toHaveYielded(['Promise resolved [A]']);
      expect(Scheduler).toFlushAndYield(['A']);