Can expect the release to be late next year, (almost 2 years) by that time the Navi 10 and Navi 10 lite will drop in price which will significantly lower the overall price of the console.
Sony co-developed navi with amd, and co developed ssd drive. In some way they own the technology, so i dont think they need to wait for prices to drop. In a bizzare way i can see Microsoft paying royalities in some way for Navi tech. We don't really know what the agreement is between Sony and Amd on Navi tech.