A few questions

Hello,
I am a candidate for USMA 2020. I have a LOE, a presidential nomination, a congressional nomination, and am 3Q'd.

My main questions are about my LOE. How common is it to receive a LOE? Will a LOE help me significantly with admissions?

Also, I believe this may have already been said in a previous thread, but when should I expect to receive a decision?

Any insight provided would be greatly appreciated