6. Section 276 of the Principal Act is amended—
(a) by omitting from paragraph (1) (b) “rights” and substituting “interests”; and
(b) by adding at the end the following subsections:
“(8) In this section—
‘person' includes an unincorporated association.
“(9) For the purposes of this section, an organisation or association of persons, whether incorporated or not, shall be taken to have interests that are substantially and adversely affected by a decision if the decision relates to a matter included in the objects or purposes of the organisation or association.”.