(iv)fifteen per cent. of such remuneration for an assessment year beginning on the 1st day of April, 2004, as is brought into India by, or on behalf of, the assessee in convertible foreign exchange within a period of six months from the end of the previous year or within such further period as the competent authority may allow in this behalf and no deduction shall be allowed in respect of the assessment year beginning on the 1st day of April, 2005 and any subsequent assessment year]:]