15. In the case of earnings of a person treated as receiving relevant education under regulation 12(b) (relevant education) and who is engaged in remunerative work, if—
(a)an amount by way of a disabled child premium under Schedule 2 (applicable amounts) is, or but for his accommodation in a residential care home, nursing home, hostel or board and lodging accommodation would be, included in the calculation of his applicable amount and his earning capacity is not, by reason of his disability, less than 75 per cent of that which he would, but for that disability normally be expected to earn, £15;
(b)in any other case, £5.