"date of assessment"

means—

(a)in the case of an assessment by SARS, the date of the issue of the notice of assessment; or
(b)in the case of self-assessment by the taxpayer—
(i)if a return is required, the date that the return is submitted; or
(ii) no return is required, the date of the last payment of the tax for the tax period or, if no payment was made in respect of the tax for the tax period, the effective date;