"the degree of disablement shall be assessed on an interim basis unless the member's condition permits a final assessment of the extent, if any, of that disablement."
"5. Appeals against assessment of extent of disablement (1) Where, in the case of any such claim as is referred to in section one, section two or section three of this Act in respect of the disablement of any person, the Minister makes an interim assessment of the degree of the disablement, he shall notify the claimant thereof and an appeal shall lie to the Tribunal from the interim assessment and from any subsequent interim assessment, and the Tribunal on any such appeal may uphold the Minister's assessment or may alter the assessment in one or both of the following ways, namely-- (a) by increasing or reducing the degree of disablement it specifies; and (b) by reducing the period or which the assessment is to be in force. In this section the expression 'interim assessment' means any assessment other than such a final assessment as is referred to in the next following subsection. (2) Where, in the case of any such claim as is referred to in section one, section two or section three of this Act in respect of the disablement of any person, it appears to the Minister that the circumstances of the case permit a final settlement of the question to what extent, if any, the said person is disabled, and accordingly-- (a) he decides that there is no disablement or that the disablement has come to an end or, in the case of any such claim as is referred to in section three of this Act, that the disablement is not or is no longer serious and prolonged; or (b) he makes a final assessment of the degree or nature of the disablement; he shall notify the claimant of the decision or assessment, stating that it is a final one, and thereupon an appeal shall lie to the Tribunal on the following issues, namely-- (i) whether the circumstances of the case permit of a final settlement of the question aforesaid; (ii) whether the Minister's decision referred to in paragraph (a) hereof or, as the case may be, the final assessment of the degree or nature of the disablement was right; and the Tribunal on any such appeal may set aside the said decision or assessment on the ground that the circumstances do not permit of such a final settlement, or may uphold that decision or assessment, or may make such final assessment of the degree or nature of the disablement as they think proper, which may be higher or lower than the Minister's assessment, if any, and if the Tribunal so set aside the Minister's decision or assessment they may, if they think fit, make such interim assessment of the degree or nature of the disablement, to be in force until such date not later than two years after the making of the Tribunal's assessment, as they think proper."
"5B Matters relevant on appeal In deciding any appeal, a Pensions Appeal Tribunal- (a) need not consider any issue that is not raised by the appellant or the Minister in relation to the appeal; and (b) shall not take into account any circumstances not obtaining at the time when the decisions appealed against was made."