Just did Sydney a few months ago and kept an eye on the loads for at least a month or so before departure. I noticed it really did not change that much, however beware of the other stand by passengers. I flew United out of SFO and their were almost 80 Standbys listed for the flight. I still got a seat in the back, but it was close. So I would keep those in mind too when trying to get out to SYD! Hopefully they will all be occupied with London and Olympics this summer. Either way, SYD was one of my best trips and had an absolute blast down under!