Once the news hit, there was a demand for a discount on the stock, for obvious reasons, with nobody willing to sell at more than a 5% discount, so there you go,

Once the news hit, there was a demand for a discount on the stock, for obvious reasons, with nobody willing to sell at more than a 5% discount, so there you go, an instant 5% move to where a buyer finally found a seller. If you're asking why sellers were willing to sell at that price, well, there were plenty of people willing to sell at a 4% discount instead of a 5% discount, but no buyers. All market participants have different opinions on the effect the news had on future cash flows, but the 5% magic number was the place where there was a consensus between bulls and bears on a fair price. The price of the stock only shows you where a consensus between a buyer and seller was reached, and doesn't tell you much about the structure of the order book or option chain for a stock, which indicates a lot more about what all market participants think about a stock.