...posting that date as the first result in the search results.
I'm not quite understanding the question. Do you mean that the date is appearing in the snippet? Or do you mean that the article is ranked first? If you're talking about regular Google serps, are you talking about the news results that appear above the serps, or in "site" serps themselves?
If you're talking about dates in the snippets, I've seen them when they're near words that are contained in my search query... but not all of these for pages cached after April 1.