(1) Subject to subsection (1A), where there is no intermediary, or the relevant taxpayer has been notified by an intermediary under section 817RC(10), the relevant taxpayer shall make a return to the Revenue Commissioners of the specified information within 30 days beginning -
(a) on the day after the reportable cross-border arrangement is made available for implementation to the relevant taxpayer,
(b) on the day after the reportable cross-border arrangement is ready for implementation by the relevant taxpayer, or
(c) when the first step in the implementation of a reportable cross-border arrangement was taken in relation to the relevant taxpayer, whichever occurs first.
(1A) Notwithstanding the time limit specified in subsection (1), the period of 30 days for making a return under that subsection shall begin on 1 January 2021 where -
(a) the reportable cross-border arrangement is made available for implementation to the relevant taxpayer,
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