If the Secretary of State so directs in the case of any scheme or any description of scheme, such of the preceding provisions of this Chapter as are specified in the direction shall not apply in relation to that scheme or, as the case may be, in relation to a scheme of that description.

The power under this section to give directions may be so exercised as to make different provision with respect to different local housing authorities or descriptions of authority (including a description framed by reference to authorities in a particular area).