The amount of effort spent on this is astounding. There was 1 (one) conviction following the general election in 2017. Of the eight cautions given out, 2 were about postal voting, four were about registration, and the other two were about candidates. So twice as many candidates as actual cases of voting fraud at the polling station.
Frankly if they put as much effort into things where a real number of people were involved (for example Universal Payments) or if they REALLY need to focus on democracy then there is a whole question about how referenda are conducted...