I would venture the opinion....If any ballot was challenged because a few papers had gone out to members who had resigned from the TU by stopping their payments, then all ballots would potentially be illegal. I don't think anyone is claiming that the numbers are significant.
In this case I think the ballot will be re-run with a different question...
Bill Francis made a very clear statement to a good friend of mine who stated they had received a ballot form despite leaving Unite months ago. He said that they are allowed to make a few mistakes as long as they aren't 'proactive'. So yes the next ballot must be run with another question.
MPN 11 - you beat me to it, and also agree with the rest