Battlegrounds Cosmetics not in Blizzard Shop

I’ve noticed with several releases now that items for Battlegrounds (the Strikes and the special boards and skins) will go up in the client but they don’t show up on the Blizzard Shop until much much later. That’s primarily how I purchase those items as I don’t make purchases through the hearthstone app and do it on the blizzard shop instead. Is there a reason why those are delayed so much? There was a release last week of a new strike and a new set of skins for Battlegrounds but they still aren’t on the site. I’m just curious because other cosmetics for the game aren’t delayed and are up the same time as they are in the app but the Battlegrounds ones are always delayed. Is there a reason why this is delayed?

What is the difference between making a purchase in the blizzard ran app and the blizzard ran website store? You can follow and track and dispute all the purchases made in app thru the website store (including ones transacted with gold and not irl money) so that isnt a cogent reason. I am curious as to why the specificity to using the website store is of any importance to you.

I don’t play on PC so I’m only on mobile. And I don’t have my credit card info in my phone so I never make in app purchases and things. (My kids are on there alot so I never used my card on there as a way to make sure nothing gets accidentally bought.) So when I want to purchase something, I go to the website to do it since I can use my card there. But it’s just odd that the Battlegrounds extras don’t show up there until much much later.