Can You Stack Chase Offers? (No)

As you know by now Chase has rolled out Chase offers, a competitor to American Express offers. One unknown until recently is what happens if you get two offers for the same store, do they both trigger or only one? With American Express the offers stack, unfortunately with Chase the offers do not stack. We know this because recently Chase rolled out a 30% at Panera, some people were able to add this to a card that already had a 15% back offer. According to the comments it looks like whatever offer expires first will be used first, but that might not be the case. If you have a datapoint that goes against this, let us know.