Why Union?

Different topic for this brand new station, called Union, but on the same Belgrave/Lilydale line. Is it called Union after a nearby road of that name, because it is the union of two former stations (Surrey Hills and Mont Albert) or because the Victorian state premier is in the pocket of the trade union movement (that's he who cancelled the 2026 Commonwealth games)? Two Metro Xtrapolis EMUs leaving for the city.