10 February 2011
In accordance with the relevant provisions of Income Tax At, Form 27C is required to be submitted by the person responsible for collecting tax on or before the seventh of the next month (following the month in which the declaration is furnished to him)
10 February 2011
Form 27 C is to be filed before the chief commissioner / commissioner and not to the AO. Due date is on or before the 7th day of the next month following the month in which the declaration is furnished to him by the buyer. As a corollary to the above, minimum validity is one day and maximum is thirty one days.