13.—(1) C meets the required period condition for the purposes of Article 84(1) where—
(a)if C had been assessed at every time in the period of 3 months ending with the prescribed date, it is likely that the Department would have determined at that time that C had limited ability to carry out mobility activities; and
(b)if C were to be assessed at every time in the period of 9 months beginning with the day after the prescribed date, it is likely that the Department would determine at that time that C had limited ability to carry out mobility activities.
(2) C meets the required period condition for the purposes of Article 84(2) where—
(a)if C had been assessed at every time in the period of 3 months ending with the prescribed date, it is likely that the Department would have determined at that time that C had severely limited ability to carry out mobility activities; and
(b)if C were to be assessed at every time in the period of 9 months beginning with the day after the prescribed date, it is likely that the Department would determine at that time that C had severely limited ability to carry out mobility activities.