I get my info from experience! It's common knowledge that you change out defensive ammo. You don't leave your ammo in your home all the time you carry it. Temperature changes, humidity and sweat can cause problems. Ammo stored in a controlled environment will last a lifetime. You also need to practice with your carry ammo. This will give you the chance to do so. I usually replace mine every 6 months. Also you don't need to rotate magazines. Magazine springs are compression springs and are designed to be compressed. Loading and unloading magazines do more damage to the springs than keeping them loaded. I have magazines that have been stored loaded for over 20 years and will work just as good as the day I loaded them.
USAF Retired, CATM, SC CWP, NH NR CWP, NRA Benefactor
To preserve liberty, it is essential that the whole body of people always possess arms, and be taught alike, especially when young, how to use them... -- Richard Henry Lee, 1787