(1)Subject to subsection (2) below, the Department may review any decision given by it on any such question as is mentioned in section 15(1) above, if—
(a)new facts have been brought to its notice; or
(b)it is satisfied that the decision—
(i)was given in ignorance of some material fact;
(ii)was based on a mistake as to some material fact; or
(iii)was erroneous in point of law.
(2)A decision shall not be reviewed while an appeal under section 16 above is pending against the decision of the Department on a question of law arising in connection with it, or before the time for so appealing has expired.
(3)On a review any question of law may be referred under subsection (1) of section 16 above or, where it is not so referred, may be the subject of an appeal under subsection (3) of that section, and the other provisions of that section shall apply accordingly.