Blacksmith101
Grumpy Old Man
- Jun 22, 2012
- 22,296
The USPS should have given you a Certified Mail receipt upon mailing.
That, along with a copy of your letter is all the proof you need.
+1 You only need to prove it was sent not prove it was received. Even if the BATFE sent it back to you unopened you still sent your application before October 1st.