Well what to say of this train, it is such a long train, usually it starts 1 hour late from Jammu and till it reaches Gorakhpur it gets late by almost 4 hours. It runs very slow in Whole Bihar route and when it reaches Guwahati it is late no less than 5 hours. So if in case you are in a hurry and very strict about the timing of train, never trust this train.
Also you can easily get a confirmed ticket in 3AC post Katihar and sure shot after NJP.

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