In this Chapter, except where the context otherwise requires -

"due date", in relation to an income tax month, means - (a) the day that is 15 days from the last day of the income tax month, or (b) the day that is 24 days from the last day of the income tax month, where the following conditions are met: (i) the return and the remittance of the amount of income tax due for the income tax month are made by such electronic means as the Revenue Commissioners require; (ii) the return is made by the return date and the remittance concerned is made on or before the day that is 24 days from the last day of the relevant income tax month;

"electronic means" has the same meaning as it has in section 917EA(1);