AP is discontinued... When they were on the Mobil 1 list as a product the 0w-20 did not show as a SP oil but all other viscosities did. As far as PP and PUP, PP goes down to 0w-16 where PUP does not. Just curious...
I think AP was a failure right from the start. It was too high priced plus it was marketed for a small majority of drivers that drive 20,000 miles or more a year. The marketing was horrible and the jugs just sat on Walmart shelves until they finally disappeared.
My thinking is that Mobil was already making lineup changes before SP started and they had already decided not to include AP.