回複：現在開始辦NIW材料還來得及嗎？

I think if you can get all letters on Sept. 26, you can catch
the time. There is an alternative/safer way to do so.
I didn't use it but someone tried.

You can do the 140/485 efiling now. I heard that you
then need to submit all other materials within 7 days.
Some lawyer even says the letter can wait until you
get RFE (but I suggest you not do it. RFE is normally
bad for any application). But since you can prepare all
documents in time, you don't need to do efiling. I am
just giving you more time in case your letters would not
come in on Sept. 26.

I used lawyer to finish my application (received green
card on Sept. 19). I might have the cover letter and
statement(?). The cover letter was written by my lawyer.
I didn't remember I wrote anything like statement but
had a contribution letter from my advisor. I will send
you an email.