I was planning to go to the international student service office of my school to pick up my new I20 for recommending OPT on July 5th 2018(the day after Independence Day) and submit the rest of the application to USCIS on the same day. However I didn’t realize until yesterday that the office will be closed through Friday, July 6th 2018, which means it won’t be open again until next Monday, July 9th 2018, which is the last day of my 60-day grace period following my program completion. Therefore, I can only submit my OPT application on the last day of my grace period to USCIS. I plan to use the same-day delivery from the post office (either USPS or UPS) in order for my application to be received on July 9th, but I don’t feel 100% secure about this, which means that it is possible that USCIS won’t receive my OPT application until the 11th (estimated with normal delivery). This will cause my OPT application to be received 2 days after the last day of my grace period. Will this work? Please help with your experiences and knowledge, thank you!