I have always held that if the voting system changes, a general election must be called immediately the law is passed. This ensures that the electorate get an immediate say in how the country should be run under the new system. A formed this opinion in the 1980’s firmly in the knowledge that if we changed to PR at the time, the Tories would suffer a a loss or a very, very reduced power base. I hold that opinion even today, in times when it’s hard to predict how an AV election would run if held this year.