This is just a way to fool masses I think. The schedule itself is kind of strange. According to the schedule, the train leaves last halt Tori at 6:45 am and reaches destination Ranchi at 11:40 am. Why should this traintake nearly 5 hours to travel a distance of just 205 km from Tori to Ranchi? Granted the route has speed restrictions but does that mean it should crawl at a speed of around 40 kmph normally? I think the reality is that the train delays a lot in its journey from Delhi to Dehri on Sone and after that, it is given this additional buffer time by this misleading schedule so that people think it is such a good train afterall. I have myself seen that this train gets much lower priority than Rajdhanis and Durontos, has long unscheduled halts in some stations along Kanpur-MGS and often gets delayed midway...
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by nearly 1.5 hours yet reaches in time in Ranchi due to this pathetic schedule.
And in those days when these unscheduled halts are not there by God's grace, it of course will reach 45 minutes ahead of time. Afterall, it can't be such a crawler!
The Rajdhani of this same route 12454 also is given a lot of buffer time and so it also is seen reaching ahead of time by 40-45 minutes often.
Unless someone explains the reasons for such huge slack in schedule of the train, I am bound to feel this is just a way by IR to mislead.