22 July 2013
1)for A.Y.2011-12 can be filed under section 119(2) --it is possible to file only if you have any refund or loss only ..and can be filed only after approval of CIT.
2)for A.Y.2012-13 can be filed belated return as per Section 139(4) However please note AO can demand Rs.5000 penalty under section 271F if you faild to submit return under section 139(1)
3)For A.Y.2013-14 you can file return as per section 139(1) with in 31st july if tax audit not applicable.