; minus (ii) the amount such new school food authority was reimbursed under the reimbursement sections for meals and supplements served by such new school food authority during such reimbursement month. (B) For each school food authority not described in subparagraph (A) in the State for the reimbursement month, an amount equal to 55 percent of— (i) the amount such school food authority was reimbursed under the reimbursement sections for meals and supplements served by such school food authority for the month beginning one year before such reimbursement month; minus (ii) the amount such school food authority was reimbursed under the reimbursement sections for meals and supplements served by such school food authority during such reimbursement month. (4) Treatment of funds (A) Availability Funds allocated to a State under paragraph (1)(A) shall remain available until March 30, 2021. (B) Administrative expenses A State may reserve not more than 1 percent of the funds allocated under paragraph (1)(A) for administrative expenses to carry out this subsection. (C) Unexpended balance On September 30, 2021, any amounts allocated to a State under paragraph (1)(A) or reimbursed to a school food authority or new school food authority under paragraph (3) that are unexpended by such State, school food authority, or new school food authority shall revert to the Secretary. (5) Reports Each State that carries out a reimbursement program under paragraph (3) shall, not later than September 30, 2021, submit a report to the Secretary that includes a summary of the use of such funds by the State and each school food authority and new school food authority in such State. (b) Definitions In this section: (1) Alternate period The term alternate period means the period beginning January 1, 2020, and ending February 29, 2020. (2) Emergency operational costs The term emergency operational costs means the costs incurred by a school food authority or new school food authority— (A) during a public health emergency