How long to request on my B2?
 

Hi,
I've downloaded the B2 visa application and am preparing to fill it out. Just after some advice really. I don't intend to go to the states until next year, can I submit the form far in advance?
My trip is for research purposes for a travel book I want to write? I want to go for at least 6 months to a year. Is this request likely to lead to rejection, what sort of timescales are the norm?

Also could anyone provide me with info about the Grandfather clause. I am over 18 so I don't think I am valid to qualify for citizenship anymore (My Grandad was born in Lowe Mass.) but what are the details about this clause?

Hope someone will be able to help

Thanks