Gunpowder lifetime is the limiting factor for ammunition lifetime. Lifetime expectancy for single based powders is 45 years and 20 years for double. High heat and bad storage conditions can reduce this life time to months.
See, paragraph 7.3, how temperature reduces the lifetime of ammunition.
United Nations (UN) Manual
IATG 07.20 Surveillance and in-service proof
I think it makes sense to rotate your stock, shoot the oldest ammunition up first.