It's none of the above.
Hot Toys changed their policy about a year ago, basically what happened was that many people who had pre-ordered their Mark IV for nearly a year suddenly lost their order due to not enough stock (flippers), those buyers then had to resort to Ebay which was already instantly marked up over $50 because they were completely sold out everywhere (again, flippers). Since then HT leaves an open ES on all their figures, then closes the production once they make sure everyone got their orders through, that's their method to counter flippers and to make sure people don't loose their pre-orders like the Mark IV fiasco.
So HT is purposefully making sure their stuff don't instantly sell out, they want to make sure people can actually buy them during release even if they somehow missed the pre-order.
Ever since this new policy, only figures labeled as "limited edition" has the possibility of selling out during pre-order (Avengers Mark VI.) All the other figures will 100% always be in-stock during release. It doesn't matter if there's 5,000 or 50,000 pre-orders for a particular figure, they'll fill all pre-orders and make a few thousand more to go around in stores for months.
--