to answer your question, i pulled this off the hrsa scholarship 2010 bulletin
it has pretty much all the answers you could possibly need for the most part. i have posted the link as well: http://bhpr.hrsa.gov/nursing/scholarship/applicantbulletin/benefits.htm
[color=#006699]defining a participant's academic school year
all nsp scholarship contracts are for a specific year. the school year is defined as july 1 through the following june 30 during which an applicant is enrolled in a school. if, for example, a student is in a 24-month program that begins on august 3, 2009, and he/she signs contracts for 2 school years, the student will receive stipend, orc and tuition payments through june 30, 2011. funding for the extra months of the program beyond june 30, 2011, would require a request for a third year of scholarship funding, and if granted, obligates the recipient to 3 full years of service commitment. if a student is in a 24-month program that begins on may 3, 2009, and he/she signs contracts for 2 school years, the student will receive a stipend, orc and tuition payments from july 1, 2009, through june 30, 2011, or the month the recipient completes the required classes for graduation, whichever comes first.
this basically means that for whatver months you were enrolled in school since july 1, 2009, you will receive a backdated stipend.
in my case, i have been enrolled since may, however i won't receive a stipend for may or june, mine will begin for july. so i should receive, july, august, september, and october plus the orc payment.
hope this helps!