(1) Section 746 of the Principal Act is hereby amended -

(a) by the substitution for subsection (1) of the following subsection:

"(1) Subject to subsection (2), sections 579 and 579A shall apply in relation to their application to offshore income gains as if -

(a) for any references to a chargeable gain there were substituted a reference to an offshore income gain,

(b) in subsection (2) of section 579 and subsection (4) of section 579A for 'the Capital Gains Tax Acts' there were substituted 'the Tax Acts',

(c) in subsection (2) of section 579 and subsection (3) of section 579A for 'capital gains tax under section 31' there were substituted 'income tax by virtue of section 745', and

(d) in subsection (5) of section 579 and subsection (9) of section 579A -

(i) for 'any capital gains tax payable' there were substituted 'any income tax or corporation tax payable', and

(ii) for 'for the purposes of income tax' there were substituted 'for the purposes of income tax, corporation tax'.",

(b) by the insertion after subsection (2) of the following subsection:

"(2A) Where in any year of assessment -