SDAH/HWH/KOAA-NJP route have either of the options
- via MBB-AZ-MLDT (Nashipur) - This is shortest route, but work yet not completed.
- via BWN-RPH-MLDT - existing one (portion of the section have MPS of 130, rest average of 100)
- via BDC-AZ-MLDT - existing one (portion of the section have MPS of 110, rest average of 95)
...
more...

For BDC-AZ-NFK:
Bandel-Katwa MPS is 110
Katwa-Azimganj MPS is 100
Azimganj-NFK MPS is 110

Based on the Journey by 03113 Hazarduari Special from BP to BPC my observation
1. This route is upto RHA mostly dominated by EMU local / passenger. But the frequency of this is reduced at late night /early morning time. So Padatik/ Dmail /Kanchanjangha will be a good option for this route .

2. First glitch between Kakinara nad Naihati...
more...

has been removed. So entire SDAH to NH is quadruple line. Train can easily take speed in this section.

3. NH to RHA 3rd line laying ( Most of the Earth work and bridge construction works) has been speedup. Halisahar , Kanchrapara, Madanpur station has been renovated for 3rd line. So third line will gain some speed up.

4. Nashibpur Rail bridge is the key of this route. I am very much sure after 2021 if the state Govt. (Inline with Central Govt. ) will help the Railways not only this other 21 railway project will be shifted from "abeyance" to active state.