Yay! I'm not alone. My 9/30 trip is not posted yet while return flight (10/4) is posted today. My case is DL flight, so I think I need boarding pass to write missing form, but unfortunately I dumped it out. I'll wait for a few more weeks before I give it up.
In the missing form, it says:
Include a copy of your ticket receipt or travel agency invoice, including ticket number and your original boarding pass (if Continental or airline partner), or a copy of your qualifying purchase receipt (if a non-travel partner)