Amsoil doesn't have a "date" expiration, it doesn't degrade or lose viscosity by sitting in a cold oil pan.
I'm running it in my motorcycle over 2 years now with 3000 miles, with no changes and it's fine.
Got any reputable sources to back that claim?
There's a reason car and oil manufacters "recommend" oil changes based on miles OR time. I'm sure most people have heard the 3,000mi OR 6 mo oil change.... 7,5000 mi OR 1 year... etc
Once that oil enters the engine some chemical changes happen from contacting the metal, mixing with the existing oils and any contaiminants/solubles/etc. More so once that engine is started and byproducts of combustion, condensates and other contaiminants are introduced to the oil. more so with lots of shorts trips, which is common for low miles over long periods of time.
Oil in a "sealed" bottle may have a very long expiration date, but that is not the same as fresh oil poured into the oil pan. Many additives are used up as part of their job fighting certain things