I knew about the Part C volatility from a posting by Photo Engineer a while back, so it is to be expected with open concentrates. But sealed, the shelf life should be at least the 2 - 3 years indicated by Sebastian. Freestyle gave me a credit for the one remaining kit that I can no longer use, and I decided to apply it toward a Maxi kit since I will need it when I return from vacation next month. According to the rep I spoke with, the issue was only with the Midi kits, and they have sent their remaining stock back to the manufacturer.
That's great to hear....I was thinking of getting the Maxi kit next time I ordered.