5.— (1) Where, before the coming into operation of section 4, a multi-unit development has been substantially completed by or on behalf of the developer, and the ownership of the relevant parts of the common areas or the reversion in the units concerned has not been transferred to the owners’ management company concerned, the developer shall within 6 months of such coming into operation arrange for the transfer of such ownership to the owners’ management company concerned of the lands referred to in section 3(1)(b), without the reservation of any beneficial interest.

(2) For the purposes of this section, a multi-unit development shall be regarded as being substantially completed if the sales of not less than 80 per cent of the residential units in the development have been closed.