100. Leaving the cash basis.

The following provisions apply if:

  1.  

    (1)     a person carrying on a trade, profession, vocation1 or property business ('the business') leaves the cash basis in a chargeable period;

  2.  

    (2)     the person has incurred expenditure at a time when the profits of the business are calculated on the cash basis;

  3.  

    (3)     some or all of the expenditure was brought into account in calculating the profits of the business on the cash basis; and

  4.  

    (4)     the expenditure would have been qualifying expenditure if the profits of the business had not been calculated on the cash basis at the time the expenditure was