Hey coffee_craver! First off, congratulations on the Brazil ETA! I will be joining you. Can't wait!!
As for airfare, we pay for it out of pocket but we have to buy an economy ticket or use our own money for an upgrade. They then reimburse us. As for arrival/departure dates, the orientation handbook says it has to "more or less" correspond around the beginning and end of the country's school year, whatever that means.
So excited to meet you! And we have a Facebook group - Fulbright ETA Brazil Grantees 2015.
Parabéns!