So, I go to hp.com and navigate to find lots of (older) models listed.
Then I click to configure and get
It says "The kit cannot be purchased at this time."
What's the point of displaying the models in the first place?
This looks like a question for HP more than AMD.
(Speculation: Maybe HP gives first dibs to retailers who make big orders, and there isn't enough supply yet to leave enough for the US HP store. I don't remember which retailer, but I've seen Aug 17th as a date some models may be shipped from a retailer, so maybe there are still a few weeks before some models will be available. AMD doesn't own its own fabs, so it may be at the mercy of fab and manufacturer schedule slips. I think HP outsources the assembly of its own laptops, so it may be at the mercy of a factory's schedule slips. Being a big brand it should have a lot of clout, but it might not use it on low-price models.)