As this is a consultative ballot on the BA offer and not a strike ballot the rules are different. If BASSA inadvertently ballot people not in the union it is an irrelevance in terms of ballot invalidation, as this ballot will not lead to IA. Even if it were for IA, BASSA only need to prove that to the best of their knowledge all people balloted were union members. If you remember the previous case, it was Miss Malone's stupidity in telling people who would not be in the company when any IA happened that they were still eligible to vote that led to the ballot being illegal. Essentially this ballot is a different thing entirely.