Westpac will continue to accept cash or eftpos payments over the counter after 1 October 2014 but they'll no longer accept any cheque payments, returns or other documents. (These will need to be either filed online or posted to Inland Revenue.)
Posted cheques must be received on time
From 1 October 2014, cheque payments posted to Inland Revenue must arrive on or before the due date to avoid late payment penalties and interest.
Direct Credit Refunds (in error)
If the IRD direct credits a refund to you in error (you may have wanted the refund transferred to another tax type), provided you return the credit within 20 working days to the them, the IRD will backdate the refund to the original date with no penalties or interest being charged. The repayment
needs to be made to the same tax type as the original refund and you need to advise the IRD (phone or email) that you have returned the payment, so they can change the date in their system to the original date.