Joe

I also doubt that SpiceJet would accept your luggage that early. IIRC, there used to be a left luggage facility at the old CCU international terminal, but with that terminal being closed, I don't think there is such a facility anymore. The CCU airport website does not list this as a facility, either:

http://www.airportsindia.org.in/kolk...enger_info.jsp

If you have to take your bag with you, you can leave it at a cloak room in the train station. That is probably the most economical. Another option is to hire your cab for the day, but that is not as cheap or fun