I’d add that provided the issues with Perth Airport get ironed out (and I’m sure they will), I would hazard a guess that capacity issues can be addressed by adding services through Perth. That would also be a far better service for those customers from Melbourne/Adelaide etc, to connect with, who don’t live in Sydney, or to the North/South Pacific/across the ditch.
Additionally it would give the option to bump a few pax onto when the weather isn’t playing ball for the direct Sydney to take all of its booked load.