They don’t really have anything to gain by delaying until October

They gain more money, because they are the only major political party that has virtually zero dollars in donations from companies. The NDP absolutely struggle when there are frequent elections, because they’re funded almost entirely by the (barely remaining) middle class, and the poor. After Harper removed the cap/guaranteed money for each party to have per election, the NDP have been so far behind the funding of the other parties it’s very sad.