Oil if kept in a tightly sealed container, in a dark place can last 10 years or more.
I run all my engines no matter what type on Comma 5/50 competition oil (motor sports).
My Toyota Avensis 2.0ltr D4D ran on this from 7,000 mls till I scrapped it with 208,000 mls on it, the engine still sounded like new.
I had to scrap it because the subframe cracked & made the car handle in a very interesting manner all the way to the scrappers

.
Yet I was told by everyone & they're mate that this oil is only meant for racing & is changed after every race, so will break down very quickly.
I changed it every 10,000 mls or less & I never do oil changes based on manufacturers specs, they are far to long between changes!!!
Sorry for the long winded post
Phill