Why can’t a membership plan cover all three branches?

The answer to this is very simple; because of your audit! A health and safety audit is only relevant to the premises at which it is conducted. Even when the operations are the same but are conducted at different premises, the premises themselves will be different and so, need to be audited individually. Factors, such as legislation, may be applicable to one premise (and its operations) but may not be applicable to another. Our audits relate singularly to a premise so they are simpler to understand and manage.