As far as the quarantine to Australia thing goes:

I was assuming that while the owner winters there, that he'd keep the horse there year rounce once he's got her there.

Not that it's any of my business either way, but that was my take on it.

(I also think it can be silly to get a horse from one side of the country when you live on the other side and then you have to buy it and transport it, etc. So a horse from one side of the world to the other also strikes me as silly but hey...I considered (briefly) transporting my horse from Maryland to Hawaii (if I could swing getting a job out there) so...*shrug!*)