I booked RAC ticket for travelling on 29th May. I reached TPJ at 3pm, train was already standing in platform 1, but they said chart not yet ready.
I waited near the train. Exactly at 3:15pm I received SMS saying chart prepared and giving my seat number. Chart was prepared just 45 minutes before departure. By coincedence, my coach S3 was exactly before me. Train left correct time and reached Howrah 40 minutes early.