If trains will be diverted, time slot between danapur to barauni and in total Delhi to destination have to be kept same, otherwise long distance passengers comfortable time at starting stations and last four five stations will not remain comfortable , also there will be requirement of additional racks.
Therefore to keep same time slot between danapur and barauni , these long distance trains should be run through sahpur patoree. At least till the time hajipur muzaffarpur doubling not takes place.

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Only 3 platforms at HJP and this will create a situation of no room. Hence trains will be stopped at Sonepur for longer durations thereby causing delays. The work of platform 4 and 5 should be completed at the earliest to avoid this.

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Hajipur will be getting a daily Rajdhani + Biweekly Rajdhani + Weekly Rajdhani.
Wow. Even better than Barauni.
North East , seemanchal ... will just increase the load on the station.

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Hajipur - Bachhwara is a single BG with trains moving at low speed due to semi dedicated line for goods trains. That might create problems for a rajdhani.
Moreover, these are not going to enhance the revenue.
Once started, it would stop at Hajipur or the rajdhani may not even stop at hajipur too and directly reach Patliputra.

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It would take more than 5 years for Hajipur-Barauni to get doubled. So the route via SPJ,MFP was better. Though MFP-HJP needs doubling immediately.
Your point is also correct.
Chhapra, Gorakhpur ko pata nahi kab denge Rajdhani

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