45 CFR 1305.7 - Enrollment and re-enrollment.
(a) Each child enrolled in a Head Start program, except those enrolled in a migrant program, must be allowed to remain in Head Start until kindergarten or first grade is available for the child in the child's community, except that the Head Start program may choose not to enroll a child when there are compelling reasons for the child not to remain in Head Start, such as when there is a change in the child's family income and there is a child with a greater need for Head Start services.
(b) A Head Start grantee must maintain its funded enrollment level. When a program determines that a vacancy exists, no more than 30 calendar days may elapse before the vacancy is filled. A program may elect not to fill a vacancy when 60 calendar days or less remain in the program's enrollment year.
(c) If a child has been found income eligible and is participating in a Head Start program, he or she remains income eligible through that enrollment year and the immediately succeeding enrollment year. Children who are enrolled in a program receiving funds under the authority of section 645A of the Head Start Act (programs for families with infants and toddlers, or Early Head Start) remain income eligible while they are participating in the program. When a child moves from a program serving infants and toddlers to a Head Start program serving children age three and older, the family income must be reverified. If one agency operates both an Early Head Start and a Head Start program, and the parents wish to enroll their child who has been enrolled in the agency's Early Head Start program, the agency must ensure, whenever possible, that the child receives Head Start services until enrolled in school.