The chief executive may assess a person over the period, and at the rate of progress, that the chief executive considers appropriate, having regard to—
(a) the need to carry out the assessment efficiently, thoroughly, to a high standard and in compliance with this Act; and
(b) the need to be fair to the person; and
(c) whether it would be appropriate to repeat a stage of the assessment process; and
(d) the timing of a possible application for an adoption order in favour of the person if the person is decided to be suitable.