Loan principle and interest in income tax

Hello,

I will get Possession of my flat in 31-Jan-2012.  I will move to my new flat in Apr-2012.  I am staying in rented flat.  I will get benefit of Principle & Interest paid on Loan EMI.  With that ...

Query:

Can I show Rent Paid Receipt for Feb-12 & Mar-12 for Tax deduction based on HRA?

So how will I get benefit of HRA say Apr-11 to Jan-12 .. Rent Paid receipt or I can get benefit of Apr-11 to Mar-12 rent receipt.

Please give your valuable suggestion.

Thanks.