Upgrades to Sydney

Last week tried to get an upgrade going LAX -> Sydney. Could get one for outbound travel on this Monday only (ok, not too unreasonable, only tried a couple of dates). Could not get a return upgrade [for miles or for certificate] until late August. Zero, zilch, nada. I wonder how long it took before they all disappeared?

Ended up flying Virgin ... we'll see how their Premier Economy feels. Delta will be partnering up with Virgin and in the future (at some point) we can get miles for these flights. They fly into Brisbane (and I don't know where else) in addition to Sydney.