Capital gains on under construction property

Hi Guys. I have a query. I booked a plot on 29th September 2011 from TDI Infrastructure for amount of Rs. 45,56,250.00 (full down payment). I also got the Allotment letter on same date mentioning the plot number allotted and size of the plot. Registration of the plot is yet to take place. I plan to sell the plot in October 2014 i.e. before registration/registry of the property.

Is the transaction eligible for LTCG indexation or any profits will be treated as STCG.

Thanks in Advance