If the necessity for leave under Alaska Stat. § 39.20.500 is foreseeable based on an expected birth or adoption or on planned medical treatment or supervision, the employee shall provide the employer with prior notice of the expected need for leave in a manner that is reasonable and practicable. If the necessity for leave under that section is foreseeable based on planned medical treatment or supervision, the employee shall also make a reasonable effort to schedule the treatment or supervision so as not to disrupt unduly the operations of the employer, subject to the approval of the health care provider of the employee or the employee’s child, spouse, or parent.