Question no. 1: In form i-821, page 3, under information about you; 25b what would be the correct answer for "Date authorized period of stay in the US expired or will expire (as shown on form I-94 or I-95). F1 student has D/S in that form but i-821 asks for specific date.

Question no. 2: In form i-765, question no. 11, what would be the answer for "Which ISCIS office?" how do we know that for OPT EAD?

I got answer for question no 2. For knowing which USCIS office, you need to look opt card. The beginning of the card number contains three letter. In my case, it was LIN---that means Lincoln service center, Nebraska. I am sharing this so that it would be helpful for any student in similar situation.

Thanks happylotus007. It was helpful. Please do update when you get answer to Question no. 1. Thanks again.

Can anybody help me out to solve question 1. What would be "Date authorized period of stay in the US expired or will expire (as shown on form I-94)"?

if its a i-94 of a student, its D/S which means Duration of Status. just type D/S

I think you can put the I20 expiration date, since duration your status depend on your I 20.

nsb, thank you for your input. At present, I have two I-20 at my hand. One MS degree I-20 that expires August 15. Another Doctorate I-20 with transfer pending from another university with expiration at August, 2020. Do you have any suggestion which date to put for the I-20 expiration?