I had a BMW 3 series with a turbo charged motor that called for a 10,000 mile oil change. I had the dealer do it when recommended by the OLM. No self destruction. I currently have a 2020 outback xt limited. I would appreciate more info, i.e. the UOA data to which you refer. This one was not indicative of an engine that was about to self destruct. I do mine at 6,000 miles with full synthetic, just in case my dealer is reading this. As for the warranty, push comes to shove, Subaru would have to prove the extended OCI was the cause of any problems if it was my car. I would like to have seen the metal flakes reported. I was in a dealer, not subaru, listening to a service rep, not the mechanic, load a poor guy with around $1,000 of total bs. I was looking shocked and the rep kept looking at me like, don't rain on my parade. I didn't, but still feel a little guilty about it.