@bigdancehawk - More than a year ago, I asked Kimberly (one of the owners of OSDIY) how she'd recommend that I store flavorings...so they'll remain at their best for the longest time. She said to store them in a reasonably cool place, away from direct sunlight and other heat sources. Been doing that since then, and I can't tell any changes in their potency, taste, etc. So IMO it's working great so far!
I also doublecheck to make sure my caps, lids, etc. are always on tightly, after I've used them, and I'm ready to stash them away. Anytime you can smell them when you open the box, cabinet, etc....either one or more has some maybe dribbled on them, or a lid's not on tightly enough.