I actually can't recall Stormblood's CE ever actually selling out, which is strange. Shadowbringers has got to be their fastest selling expansion yet considering they were out of stock just days after they went live on the site. At least one of the physical CEs went back up for a short time but sold out again. So...it's hard to say whether they'll get more in stock. If they do I'm guessing it would be a month or 2 after the expansion launches.