At the 2013 election Abbott promised that there would be no action on SSM in the next term of parliament. When he promised the plebiscite he stipulated that it would be held after the 2016 election, consistent with the promise that there would be no action in the existing parliamentary term. When Turnbull took over he did a deal with a conservative group in the Liberal Party to honour Abbott's promise to hold the plebiscite after the 2016 election...so it wasn't on the ballot paper.
