MacRumors has a report on the supposed compromises necessary on the new A18 Pro MacBook to hit the lower price point.
The 512GB storage max is what jumped out at me, and is consistent with my pricing projections.
Just two configurations: 16/256 for $799, and 16/512 for $999. No RAM upgrades, no build-to-order for Apple to manage, just two SKUs in four colors that they ship out "as is" to all the stores. If one color is less popular, Apple makes a little less of them until the channel equalizes.
Want a 1TB hard drive? That'll be in a $1399 MacBook Air. Just as before, no price increase.