I am French, and I am currently working in the US as a postdoctoral researcher under a J1 visa. I am planning to go back to France in August for research purpose, but I don't know exactly what document I need. I am especially trying to find out if there is something special to do for a more than 30 days leave, and what is the exact definition of the 30 days limit.
I have a valid visa, a valid DS2019, and a signature on it which allows me to travel. However until now, all my travels were way less than 30 days so I never had to solve this question. But to my understanding, if I am traveling more than 30 days I need a special document to be signed.
Question 1: Is that true and if yes, what is that document?
The tricky thing in my case, is that I would like to travel exactly 30 days (flights are cheaper on the selected dates than happen to be exactly 30 days). So I have 2 questions:
Question 2: What happens if my first flight US->France leaves US at 1pm on July 30, 2016, and I am flying back on August 28, 2016, arriving in the US at 11am (if I am not mistaken it corresponds exactly to 30 days, and is less than 30*24 hours)?
Question 3: What happens if my first flight US->France leaves US at 1pm on July 30, 2016, and I am flying back on August 28, 2016, arriving in the US at 9pm (if I am not mistaken it corresponds exactly to 30 days, but more than 30*24 hours)?