it seems you're right from the heart of Paltanbazar,so let me ask you a few questions::
The GHY CD right next to GHY station I think has max pit lines,if so please confirm the No.
I've noticed two more Pit line base near NGC while going towards DBRG....The one which comes left to us mainly caters to North East & Bangalore GHy etc while the one which comes right(i.e. adjacent to NGC Goods yard) caters to Lohit,Amarnath etc.. Am I ryt?
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as you're saying NGC CD people are more active,day before yesterday SBC GHY arrived GHY @ 21.45,still 2510 on the next day departed @ 12.55,why they took more than 15 Hrs to service a rake? it must be done within 7-9 Hrs
In total GHY has so many yards & pit lines ,just they need to speed up the work & proper planning

Actually I did my 11th and 12th from B. Barooah College, so we used to visit GHY CD in our free time.
GHY CD has 2 pit lines, but only one has side washing facility that also from one side. Condition is horrible.
Secondly, these days NFR is running many specials with the rakes of GHY - South bound trains, these trains are like Kamakhya - Chennai, Kamakhya - YPR Special etc. that is why running of the GHY - SBC Express and its cousins are hampered.
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the rake of south bound trains were given 1 day off at NGC yard, i.e. if SBC GHY arrives GHY on Sun, then it is allowed to leave GHY as GHY - SBC on Tue, Mon is "off". But now this arrangement is not working due to running of the specials.

No No you're misunderstood somewhere....neither of the KYQ YPR/KYQ MAS Specials are using Southbound rakes....because South bound trains are all 24 coacher with multiple 3A's..but the above 2 specials are 15-16 coaches..also with Trn No. 02507/08 KYQ MAS Special I thought once it might be using GHY ERS rake,but the days of run of both the trains are completely not allowing any kind of RSA to occur...also GHY CD has at least 4 pit lines(GMap suggests upto 7 sidings,not sure though if they're pit lines or not)...because last time when I was returning by 14055,we had a customary outside GHY just beside the CD & I noticed rakes of 5609,5658 & some unknown express were getting washed & another line was lying vacant.So 4 Pit lines are my assumption,also there is a siding near Noonmati,where serviced rakes are kept idle.
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ur theory of GHY SBC 'one day off' doesnt match with the existing rakes & the recent cyclone 'Phalin' attack..if GHY SBC has a spare rake,then the Mon dep wouldnt have been delayed because Sun Train arrived with excessive delay.GHY ERS/GHY TVC/GHY SBC has completely different CC,the difference in AC coaches proves it.
Another thing I failed to understand that North East has a spare rake(I'm sure as I've seen two rakes simultaneously,one @ PF#4 another @ NGC),then why North East starts late from GHY once in 2 weeks !!!
Trains which starts from DBRG/KYQ are far more punctual than those start from GHY
Please refer to the attached pic,it can be clearly seen that 7 trains can be accomodated in GHY CD simultaneously(NGC CD without taking into account)which is not possible @ many of the 'A' category stations in IR