I think this VB will be extended upto ERS from CBE, once MPS of 110Km/hr is acheived/upgraded b/w Shoranur and Ernakulam Jn. That's the only thing stopping them from introducing it as ERS-SBC VB and that's why IR too allotted it to SR instead of SWR planning Mrng Dep from ERS, I guess.
What do you think?
In shatabdi matter - Like you said, some shatabdi's which are having poor occupancy records will fade away in future for sure. Railways already announced, VB as a replacement for Shatabdi's and Rajdhani's.