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.
span('Sync'),
      span('Loading outer...'),
    ]);
    
    ReactNoop.expire(300);
    await advanceTimers(300);
    expect(Scheduler).toHaveYielded(['Promise resolved [Outer content]']);
    expect(Scheduler).toFlushAndYield([
      'Outer content',
      'Suspend! [Inner content]',
      'Loading inner...',
    ]);
    
    expect(ReactNoop.getChildren()).toEqual([
      span('Sync'),
      span('Loading outer...'),
    ]);
    
    ReactNoop.expire(500);
    await advanceTimers(500);
    
    
    expect(ReactNoop.getChildren()).toEqual([
      span('Sync'),
      span('Outer content'),
      span('Loading inner...'),
    ]);
    
    ReactNoop.expire(1000);
    await advanceTimers(1000);