106The designated period
(1)Subject to subsection (2), the designated period, in relation to expenditure incurred by a person on the provision of plant or machinery, is the period of 10 years beginning with the date on which he first brought the plant or machinery into use.
(2)If the person who incurred the expenditure ceases to own the plant or machinery before the end of the 10 year period, the designated period ends on the date when he ceases to own it.
(3)For the purposes of subsection (2), a person is to be treated as continuing to own plant or machinery so long as it is owned by a person who—
(a)is connected with him, or
(b)acquired it from him as a result of one or more disposals on the occasion of which, or each of which, the qualifying activity carried on by the person making the disposal was treated as continuing under one of the relevant provisions of ICTA.
(4)“The relevant provisions of ICTA” means section 113(2) or 114(1) (effect of change in persons carrying on a trade etc.).