Common thing though with the majority of online retailers except the big ones like CRC who have a massive warehouse of stock (mostly in sizes/colours most people don’t want 😉 ).
A lot will quote “in stock” to simply mean they either have it actually in stock, or their distributor stock system claims they can get it in a day or two. Either way if they have a few days turnaround then they believe they can satisfy the order.
Have been hit a few times from a number of online stores, inc Tredz I think, where it turned out the distributor was actually out of stock. I’d then tried a few others claiming in stock and they also came back saying it was actually out of stock, all because it’s the same distributor so out of stock everywhere but the system was wrong claiming it was in stock. Some had taken the money up front and had to get it refunded, and some only take payment on shipping.