Yes, most likely these ammo mfrs signed contracts months ago.
Although, I would like to get name brand ammo at reasonable prices instead of this foreign crap that is being sold now.
Companies like Olin (which is the parent of Winchester) probably have some sorts of contracts or agreements that go back a century or more (Olin at least 80 something years, Winchester 140+).
You don’t walk away from things like these based on something someone posts on the Internet.