ORS4 No.1001 is specific to UK (i.e. non-EASA) PPL holders and seeks to extend to CRIs the exemption already in place for FIs to permit remuneration for flight instruction. The restriction to a 'club environment' is utterly meaningless as there is no definition of a 'club'. The instructor and student may set up a 'club' in which they are the only members and which exists only for the duration of the training.
EASA PPL holders with instructor ratings are not restricted to instructing in a 'club' environment but, since almost all instruction is now confined to an ATO, this doesn't make a great deal of difference.