I had this issue. Your federal income tax return, which includes the lump sum loan payment, will determine your monthly payments. I have not tried to have them calculate my IBR based on my monthly income, so I don't know how successful it is.
Depending on how much your award is, the point may be moot. My payments from the NIH LRP are higher than what my monthly repayments would be (even with the higher annual incmoe), and it pushes my "next payment due date" to later dates. Bottom line, I haven't needed to make any payments since starting the LRP.
However, I think that these payments from NIH LRP do NOT qualify as qualifying payments for IBR loan forgiveness. I've heard some people try to also make "qualifying" payments in addition to the NIH LRP payments, but am not sure whether or how this approach works.
Good luck!