16. This Part shall apply in the case of a student who attained the age of 26 years before the first year of the course in respect of which his award was originally made and who—
(a)started the course before 1st September 1996 and in the three years immediately preceding the first year of the course earned or received by way of such unemployment benefit, or income support as is chargeable to income tax under section 617 or 151 respectively of the Income and Corporation Taxes Act 1988(1) sums totalling at least £12,000; or
(b)started the course before 1st September 1996, held an award in respect of his attendance at a previous course and had earned or received such sums as are mentioned at sub-paragraph (a) in the three years immediately preceding the first year of that previous course; or
(c)started the course on or after 1st September 1996, immediately before starting that course (disregarding any intervening vacation) attended a full-time course of further or higher education which he had started before 1st September 1996 and had earned or received such sums as are mentioned at sub-paragraph (a) in the three years immediately preceding the first year of that previous course.