Slow for departure time at RNC: 12873 just after it and 12366 just after 12873. In the days of absence of 12873 more than 20-25 minutes delayed 12020 can catch schedule within CRP very easily, it does not mean it is impossible in other days and it also does not mean more than 20-25 minutes make up is impossible within CRP in any day so, I used theword 'easily".
Inflated time RNC - CRP: RNC - CRP/TELO: suffering behind 13320 having more halts and longer halting duration at BKSC of 13320. It may not be difficult to make 12020 faster by solving this problem without increasing total journey time of 13320 and changed schedule of 13320 is needed without making changed time...
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of 13320 between RNC - MURI/ Pundhag /BKSC and GMO onwards.
Inflated time around GMO: GMO: struggling because cross connection with 12802, 13167, 12281 (less disturbing for 12020), 12273 (maybe less possibility till diverted via PNBE soon and no problem here after diversion)
INFLATED TIME between DHN - ASN: STN: suffering because cross connection with 13049, 15047 or any one on its day of absence, 13049.
Problem for RNG halt: If it does not halt, generally speed may not be low (maybe not 130 km/h - don't know) and generally few minutes loss for deceleration before halt and acceleration after halt than that of a non-stopping train of same category and max. permissible speed. Lower loss for WAP7 than WAP4. It overtakes 53062 Waria area - maybe extra time is not added for it in 4 line area or slightly added before ASN or after DGR.
INFLATED TIME between DGR - HWH: BWN chord: suffering for slow suburban trains is usual for most of the Mail/ Exp and not the pressure of busy time of suburbun trains and this pressure is average on that time but reversible line is busy because many Mail/Express from opposite run that time.
Trains have to wait for crossing. Suppose a car is running through left lane and another car coming from opposite direction in right lane and now the first car wants to change the road and will take right turn to do so. Both cars can’t cross a place together at the same time in the crossing but if there is a flyover, there will be no crossing with car coming from opposite direction. Khana has a flyover. Seeing google map I guess there may be a flyover in Sitarampur area but it is not always adjacent to normal route and there is a gap between flyover and normal route so time will be more through flyover than ground level if ground level track is clear. On time running may not be responsible to halt or slow running for cross connection always but schedule may be based on probable and within normal limit delay.

NTES said 31 minutes before schedule arrival at Howrah on 30 nov 2017
Train 12020 started RANCHI on 30 NovPress escape to close
Station Sch
Day Sch Arr Sch Dep ETA/
ATA Delay ETD/
ATD Delay Distance PF...
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1. RANCHI(RNC) 1 13:45 13:45 RT
0

2. MURI(MURI) 1 14:53 14:55 14:53 RT 14:55 RT
63

3. BOKARO STL CITY(BKSC) 1 16:00 16:05 16:00 RT 16:05 RT
115

4. CHANDRAPURA(CRP) 1 16:33 16:35 16:34 1 min 16:37 2 min
130

5. NSC BOSE J GOMO(GMO) 1 16:57 17:17 16:56 RT 17:17 RT
147

6. DHANBAD JN(DHN) 1 17:43 17:48 17:43 RT 17:48 RT
176

7. ASANSOL JN(ASN) 1 18:40 18:42 18:44 4 min 18:46 4 min
235

8. RANIGANJ(RNG) 1 18:56 18:57 18:57 1 min 18:59 2 min
253

9. DURGAPUR(DGR) 1 19:14 19:16 19:13 RT 19:16 RT
278

10. HOWRAH JN(HWH) 1 21:30 20:59 RT T
436
Last updated 21:15