My son and girlfriend plan to go to Australia for their "rite of passage" trek in October. That's fixed. When is the best time of year to purchase the ticket? I'm the frequent flyer - he's not - so I should know these things. But I have very infrequently traveled to Oz, it's been for business, and I've only had the opportunity to buy at 2-4 weeks ahead. Can we do better?

Thank you.