Subject to the provisions of §B of this regulation, a preschool or school, public or private, shall temporarily admit a student to or retain a student in a preschool or school if: The student is homeless; or The student's parent or guardian is unable to provide proof of immunization pursuant to the requirements of Regulation .03 of this chapter. In order for a student to be temporarily admitted to or retained in a preschool or school, the student's parent or guardian shall present evidence of the student's appointment with a health care provider or local health department to: Receive a required immunization; Reconstruct a lost record; or Acquire evidence of age-appropriate immunity on a form provided by the Department. The date of the appointment pursuant to §B of this regulation may not be later than 20 calendar days following the date the student was temporarily admitted or retained. A preschool or school, public or private, shall exclude from school a student who has been temporarily admitted or retained on the next school day following the appointment date if the student's parent or guardian fails to provide evidence of required immunizations.