"Even ICF rake Himsagar Express does 2h 40min in BZA- NLR section."
** It might be on paper, in ground reality it's not at all possible.
Take one more example of 18048. It takes 29 minutes to cover 60KM from BZA to EE with an average of 123kmph with an ICF rake. Do you think it's possible?
** Let it be anything or...
more... any reason, with current TT, extension to Nellore is not at all possible.
** You may continue on this and over to you.