Exact same thing happened with Black Widow on Aussie sites, listing for it was up on JB's site for a day and then disappeared, and there's nothing on JB any more. Sanity also had three versions of BW listed but now all that's left is the same DVD one they'd had up for over a year now. Guess we'll just have to keep our eyes open.
Regarding international shipping from JBAU, I'm in NZ and they send me single copies in a cardboard envelope (nothing fancy but in the 4 weeks it took to get here the steelbook was perfect) and bigger orders in a small box with air bags.
I believe that Disney no longer allows physical releases of their new movies to be listed for sale more than a month away from the Blu-ray/4K release date. This started a few movies ago I believe around the time of Mulan/New Mutants or maybe later.
When they do pop up for sale early, all the listings seem to disappear from all online sites (Best Buy, Amazon even eBay). I've noticed this in Canada and other places and now Australia.
Lately the pre-order listings can show up as little as 2 weeks before the release date in North America now.