Sure, you like drinking canned Diet Pepsi that was prepared who knows when from who knows what and shipped who knows how far who knows how long ago. But sometimes your Diet Pepsi gets that... not so fresh flavor. It's almost as if there's something—what's the word I'm looking for?—natural in there.
The new Pepsi version is intended to have the same overall taste, according to the person, who requested anonymity because she wasn't authorized to speak publicly. But it uses a mix of artificial sweeteners, including ace-K, that has a longer shelf life. Aspartame on its own is more sensitive to heat, which is a problem when sodas are sitting in trucks or waiting to be shipped to retailers.
Your demand for older, more artificial Diet Pepsi has been answered, America. The free market works.