Both Padatik & Darjeeling mail are extremely popular among passengers of Kolkata Siliguri sector
It was extended because locals of Haldibari NJP section demanded a overnight train to Kolkata as during its ICF days a slip service used to run between NJP & HDB & after cancellation of that slip train in ZBTT they were facing problems . So Jalpaiguri MP requested RM back in 2021 Bengal elections to sanction a overnight train from Haldibari to Sealdah & Railways approved Darjeeling Mail's extension