TDS registration

Hi, 

I've to pay sales commission to a person for Feb, March months which cross the limit & I've to reduce TDS as per rule. 

I don't have TAN and have to apply now. 

Can I apply for TAN in Apr month(new financial year) & reduce TDS amount for March month & make payments and file TDS return by May end. OR I've to get TAN number in the same financial year itself. 

Thanks in advance