The Homeland Security web site says 6 months for home-bottled water (bottled with a bit of chlorine), 1 year for commercially bottled water, and 1 year for store self-filled bottles so long as they use "ozonation" to kill nasties in the water.
I'd probably home-bottle and rotate every 4-6 months. If home bottling, make sure you clean the containers first by washing in hot soapy water. Sanitize them with a 1 tablespoon chlorine bleach per gallon of water solution (~200 PPM), shake it and let it sit for a few minutes (at least two). Rinse out the container with clean water.
For storage add 5-7 drops of 5.25% chlorine bleach per gallon of water (~5 PPM) and store in a cool dark place.