This train is always known for running late...
It left from Howrah late as may be rake at Howrah arrived late as Allahabad - Mughal Sarai section of North Central Railway (N.C.R) is notorious for making trains wait as it's highly congested and it's saturated to full extent...
It would had been nice if you had booked ticket in 12809 HOWRAH MAIL. VIA NGP, as this train is far better than it's counter part 12322 KOLKATA MAIL...