What is the sequence of payment of tax where that taxpayer has liabilities for previous months also?

Section 49(8) prescribes an order of payment where the taxpayer has tax liability beyond the current return period. In such a situation, the order of payment to be followed is: First self-assessed tax and other dues for the previous period; thereafter self-assessed tax and other dues for the current period; and thereafter any other amounts payable including any confirmed demands under section 73 or 74. This sequence has to be mandatorily followed.