पूजा सुपरफास्ट - हर रोज़ चलूँ मैं तेरे साथ मंज़िल मंज़िल - by Shubham Yadav

Shed Staff is "reluctant" to give regular loco for diverted trains as there is no guaranteed time frame in which this loco will return back to home shed / station. In case of delays, their regular links will be disturbed and they will have to allot different locos to further regular trains. Hence, they prefer to send any available / extra loco with such trains. Also, as rightly pointed by Rohit, there are other "operational" reasons. For example, when Jhelum Exp was made to run via KYN-BSR-BRC Route, E Loco was given instead of usual D Loco (PUNE WDP4D) which is needed on Pune-Daund-Manmad non-electrified section! This E Loco was also given because luckily it was available as extra loco at Pune. If not, they would have given any other shed's available D Loco (Alco or EMD) to Jhelum Exp.

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