The Manual for my 2019 Jeep states never leave engine oil in beyond 12 months. I’m assuming Chrysler states this because the oil gets caustic an can be detrimental to some internal engine parts even if you have not maxed out on the oil’s mileage rating. Is this assumption correct.
If you're not driving a new vehicle enough in 12 months to require one oil change, you should probably sell it.
Time after time it has been shown that the calendar does not dictate OCIs, but the amount of driving and conditions of that driving.
Agree that the owner's manual is written for people that never do anything but put gas in.