new part-time employee factor described in subparagraph (B). (B) New part-time employee factor For purposes of this paragraph, the new part-time employee factor shall be equal to the result obtained by dividing— (i) the hours of service that the employer reasonably estimates that the employee will have during the current plan year, by (ii) the hours of service that the employer reasonably estimates that a full-time employee would have during such plan year. (4) Restrictions regarding new employees permitted In the case of a new employee, the employer may restrict the employee’s right to use compensable leave during the first 90 days of employment with the employer. (c) Use of compensable leave In a qualified flexible workplace arrangement plan the employer may— (1) determine whether the use of compensable leave at the time requested by an employee would unduly disrupt the operations of the employer