Offsetting Capital Loss, page-32

Mundo. I used My Tax to submit my spouse's tax return. It included a lump sum payment in arrears under E on the payment summary. Unfortunately when it asked which tax year this related to, I incorrectly put 2017/2018 (when the payment was received) rather than 2016/2017 which was the tax year the payment related to.

Is there a need to amend the tax return to correct this, or is it inconsequential to the net tax payable/refundable.