PART 3Supersessions
CHAPTER 1Grounds for supersession
Error of law, ignorance, mistake etc.24
A decision of the Department, other than one to which regulation 25 (decisions against which no appeal lies) refers, may be superseded where—
a
the decision was wrong in law, or was made in ignorance of, or was based on a mistake as to, some material fact; and
b
an application for a supersession was received, or a decision was taken by the Department to act on its own initiative, more than one month after the date of notification of the decision to be superseded or after the expiry of such longer period as may have been allowed under regulation 6 (late application for a revision).