Where, by reason of the provisions of regulation 7(4) of the Prescribed Diseases Regulations, the decision on a recrudescence question necessitates the review of a previous assessment of disablement, the adjudicating medical authority may review such previous assessment, as provided by section 45 of the Administration Act, so however that, in any such case, notwithstanding the provisions of subsection (7) of that section, a previous assessment may be reviewed as provided by this regulation at any time without the leave of a medical appeal tribunal.