I'm a big fan of valvoline/Napa lubes personally, especially their HM lineup and "conventional" oils and just like knowing that they're an American company made here. I would have no issues at all pushing their advanced syn line past 6k even for the right car and conditions, and frankly that should be easy for it to do as long as it's not a GDI in severe conditions etc.
But is it any better for a 6k OCI than every other certified full syn on the shelf? As we all know by now that's highly unlikely lol!
My only gripe is that while their VWB and their red bottle HM blends are usually a solid value (excluding supertech of course) their Advanced rarely seems to go on sale and usually a "premium" price year round....hence why I said Napa too earlier
. And since Napa branded oil is almost the same stuff, I have a UOA posted from a few months back from my brother's 2017 Forrester XT with direct injection with 6k miles on the oil in severe conditions through winter here in the Colorado mountains, and it did great and stayed in grade.
Use it, or any other brand and you'll be just fine.