Regarding Tax benefit on Home Loan payment.

Hi Sreekanth I have booked a flat in noida and taken icici home loan (26.5 Lakh) in May 2013. Possession date was MAY 2016 but still we are waiting for possession. As per my understanding we can take tax rebate on home loan after possession along with previous 5 years but there are no chance of getting possession of my flat in future 2 or 3 Years..because construction has been stopped by builder last 2 years and people files case against the builder. No clarity in future and EMI is still going on. So we can't wait till possession because every year i am paying 3 lakh loan repayment amt and rent as well. I have pay PRE-EMI from JUNE 13 to JAN 15 (20 Installments) I have pay EMI from FEB 15 to till JULY 17 (29 installments) Total 49 installment (more than 4 years) i have payed .now my question is this : 1.) Can i take tax rebate of all previous years now in Assessment year 2017-18 (Before JULY 31st 2017)? Request you to please suggest possible way how i can get benefits of previous years and current year?? Thank You! MANOJ 98713704**