Delhi based Premiums are failure from kolkata because there are already mane hi class trains to Delhi 3 Rajs,2Durontos. Wealthy people settle down there. Premiums will only come in handy in festive season in HWH-NDLS route !!
There is no need of 4th rajdhani for kolkata ! But I would say an AC EXP or GR may come in handy in usual days too !! And yea your suggestion for premiums during puja is right but 1 would be enough if made daily for a week !!
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