The IRD grants this to tax payers who are linked to a tax agent (like Beany) or those who apply directly with Inland Revenue.
This extends the filing date of income tax returns to 31 March following the tax year end, giving you an extra nine months to file your returns.
It also extends the payment date of terminal tax to 7 April the following year, instead of 7 February.
EOT can be removed if you do not file or pay on time, or you no longer have a tax agent. This means that you must file your income tax returns by 7 July following the tax year end and pay your tax by 7 February the next year.