As info. I filled mine out on 9/13 (Sun), so they weren't actually mailed until 9/14. They're stamped on the back 9/17, so I assume that's when they were opened. Approved on 9/25, and I got them back today (10/5).
"All lawful reasons" was accepted. They also took my modified form with 8 firearms listed. Also didn't matter that two of them don't match the F1s, as far as lengths and/or caliber are concerned, and I've never notified them of any changes.
Only problem I have is one of them forms has TW in the Approved box, but Terry forgot to sign and date it. I've sent them an email with a scanned copy, and hopefully they'll either email me one back, drop it in the mail, or I told them I was fine with an email reply that said "approved" and I'd just stick it with the form. Shouldn't really matter, as if an agent called to verify the SN it would show approved for travel.
Here's what it looks like: