; and (C) a budget justification that estimates the supplemental funding necessary to provide for incremental ongoing operating costs for the extended hours of service under such a program schedule for the current enrollment in the agency's Head Start programs. (2) Exceptions (A) In general A migrant and seasonal Head Start agency may apply for a grant described in subsection (a) without meeting the requirements specified in paragraph (1) to ensure continuous Head Start services are provided to children enrolled in a migrant and seasonal Head Start program. To be eligible to receive the grant, the agency shall submit an application at such time and in such manner as the Secretary may require. (B) Priority In making grants under this paragraph, the Secretary shall give priority to a migrant and seasonal Head Start agency operating for fewer than 8 months per year. (c) Use of funds (1) In general A Head Start agency receiving a grant under this section shall use the grant funds to cover the costs associated with extending those hours of service for the current enrollment, such as additional costs for— (A) the purchase, rental, renovation, and maintenance of additional facilities; (B) ongoing purchases of classroom supplies; (C) staff providing services during the extended hours; and (D) professional development to staff transitioning to providing services during the extended hours. (2) Exception The Head Start agency shall not use the grant funds to expand the number of children served in the Head Start (including Early Head Start) programs of the agency. (d) Reservations (1) Activities From the total amount appropriated to carry out this section, the Secretary shall— (A) for making grants for the activities described in subsection (c)(1)(A), reserve $3,600,000,000 of the funds appropriated for fiscal year 2018; and (B) for making grants for the activities described in any of subparagraphs (B) through (D) of subsection (c)(1), reserve— (i) $276,000,000 of the funds appropriated for fiscal year 2018