Ask HN: How do I expedite Apple App Store review?

I've created an app for a client, which is going to be presented at a big event next week.

Unfortunately, when I requested an expedited review, we got rejected because of the high volume (iOS9).

Is there anyone who can help me out here?

Thanks a bunch.

PS: yes, I know we should have submitted way earlier, but there are quite some reasons why it didn't go that way.