Subject to the next following sub-paragraph, expenses incurred in carrying out any work shall not be treated as having been reasonably incurred as mentioned in paragraph (b) of subsection (1) of section twenty-two of this Act, if the work was begun more than fifteen years after the end of the period of occupation.

The preceding sub-paragraph shall not apply to any work required for making good damage caused by the settlement of soil replaced in the course of restoring the land or any other damage to the land caused by subsidence which is attributable to anything done in the exercise of rights conferred by the compulsory rights order in question.