; and (II) not later than 30 days after the date the borrower's income estimate is adjusted after an appeal under paragraph (1)(E). (ii) Borrower A borrower may request that the Secretary update the borrower’s income estimate to adjust monthly payment amounts pursuant to subparagraph (E) or (I) of paragraph (1) at any time. (d) Borrower repayment (1) Repayment period The repayment period of a loan in the repayment plan under this section shall— (A) begin on the first day of the first taxable year that begins after the borrower’s in-school deferment period; and (B) continue until the loan is paid in full, except that the Secretary may grant a borrower deferment of the borrower’s annual repayment amount— (i) for a period not to exceed 60 days, due to administrative or technical reasons; (ii) for a period not to exceed 3 months, due to unusual circumstances that disrupt the borrower’s ability to make timely payments on the loan; or (iii) renewable at 12-month intervals for a period not to exceed 3 years, due to documented extreme economic hardship on the part of a borrower. (2) Prepayment authorized A borrower shall have the right to prepay all or part of such loan, at any time and without penalty. Any such prepayment amount shall be applied in accordance with section 455(r)(3)(C). (3) Determination of income-Based repayment obligation (A) In general The repayment obligation under this section with respect to an individual for any taxable year is an amount equal to 10 percent of the amount by which— (i) the individual's, and the individual's spouse's (if applicable), adjusted gross income