Seems like she is rushing it a bit, why not enjoy the newly acquired reign a bit?? Wasn’t Rudd from a different party? How did the PM party switch happen - seems like the lower House of Parliament would have to change hands first?
Rudd was the same party - Julia Gillard was his Deputy Prime Minister. About a month ago, they realised he wasn’t popular so his party dumped him and replaced him.
There was no need for a vote if the House because Labor controls the House, and they’d elected a new leader. It’s happened before - though never so early in a term. Parties can replace their leader, and if they are in government, that leader becomes the new Prime Minister.
By going to the polls tomorrow (if she does) Gillard is hoping to be reelected for three more years. She has to go fairly soon anyway, and at the moment she still has some electoral goodwill she may lose if she waits.