Where The Employer Determines. (a) Where on the job training of 150 hours, in addition to the usual orientation period or less would be unavoidable in order to fill a existing Regular vacancy by any displaced Nurse(s) and any junior Nurse(s) who may potentially be displaced due to the Displacement Procedure in Article 11.10, such on the job training of 150 hours or less shall be first offered to the most Senior displaced Nurse.