If Patna to Howrah Jan Satabdi train can be operated which is 537 kms then why not Patna to Lucknow Jan satabdi train can be operated which is 530 kms ??
PNBE - PPTA - PAHLEJAGHAT - CHHAPRA - SIWAN - DEORIA - GKP - BASTI - GONDA - LKO
This route is fully Electrified now that's why the new Jan Satabdi train is feasible.