Carriers usually apply cost adjustments within a few weeks. Dating back to July is very odd. Is $264 for one label or a cumulative cost? Which shipping carrier @magroy1939 ?
Oh wait, never mind. I see you're in Australia - that changes things as I'm not familiar with timelines for Australia Post or other carriers available to you.
I suggest taking your inquiry over to community.ebay.com.au - you're currently on the .com forum so advice you receive here may not be relevant to your situation.
