Koi zarurat nahi hai. Agar ye bhi chandigarh gayi toh barbaad ho jayegi. Baaki trains ki tarah. Delhi bas apni trains ko priority deta hai north bound trains late hoti hein zada. eg Malwa, MDU DDN, Andaman, Kalinga Utkal, Punjab Mail, Jhelum, Hirakund etc. even chandigarh ksk.