RS77

Your expected to apply within 90 days for AOS, but there have been people that wait, 4, 6, 8 years to do this.  If your going through the Raleigh NC office it is one of the fastest in the country, we got our green card in 78 days.
 
You can't file for AOS until after you have a marriage certificate. (after your married).

Mailed AOS Package on Feb 8th and were approved on May 2th.  We were notified of interview date  in Early April, Received temp travel/work earlier in mid April as well.  The other person we knew in state also got a under 3 month file to approval.  Everyone was super nice and interview was a breeze.  Asked for copy of marriage license, asked her the names of my kids and about 20 "are you a criminal type" questions. 

Mailed AOS Package on Feb 8th and were approved on May 2th.  We were notified of interview date  in Early April, Received temp travel/work earlier in mid April as well.  The other person we knew in state also got a under 3 month file to approval.  Everyone was super nice and interview was a breeze.  Asked for copy of marriage license, asked her the names of my kids and about 20 "are you a criminal type" questions. 

Mailed AOS Package on Feb 8th and were approved on May 2th.  We were notified of interview date  in Early April, Received temp travel/work earlier in mid April as well.  The other person we knew in state also got a under 3 month file to approval.  Everyone was super nice and interview was a breeze.  Asked for copy of marriage license, asked her the names of my kids and about 20 "are you a criminal type" questions. 

Nothing original is required for the interview, not sure why the original poster has a need to do this unless it is some unique situation.