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If 130 MPS and LHB alloted to Magadh Express then time saving of Magadh
1. NDLS ALJN Section- No time saving because reason of delay is EMU trains and they will restrict other trains as usual.
2. ALJN TDL section- Total 7 minutes saving and Gap with Vaishali become down from 15 minutes(present) to 7 Minutes so crawling at outer will affect and just 2-3 minutes saving will be.
3....
more...

TDL ETW Section- 3 Minutes saving in Shikohabad Etawah section considering no TSR/PSR.
4. ETW CNB Panki Section- 8 Minutes saving considering no TSR/PSR
5. Chakeri Bahmrauli Section- 15 Minutes Saving considering no TSR/PSR
6. Naini Vindhyanchal Section- 4 Minutes saving considering no TSR/PSR
7. Mirzapur Jeonathpur Section- 4 Minutes saving considering no TSR/PSR
8. MGS ZNA Section- 2 Minutes saving
9. DLN BXR Section- 1.4 Minutes saving
10. DURE BEA Section- 1 Minute saving
No benefit in other remaining sections
Total Saving= 35 Minutes if Vaishali will not overtaken and 40 Minutes if Vaishali will be overtaken.
I think this time also can not help Magadh to run ontime because in long sections, there must be some PSR,TSRs also.