§ 23. "That any Act of the present Session making amendments of the law relating to excess profits tax in the case of interconnected companies may contain provisions (applicable to any year of assessment Income Tax for which is affected by trading results for a period with respect to any part of which excess profits tax is chargeable) prescribing the way in which payments and allowances made under those amendments are to be dealt with for Income Tax purposes, and varying, in connection with such companies, the provisions of the Finance (No. 2) Act, 1939, as to the relation of excess profits tax to Income Tax."