No one at all, should have EVER believed that the December 2016 date would remain accurate. First, it's Larian, and they like to polish games to the very last minute and then decide to push the last minute back for more work. Second, that date was given out at the start of the Kickstarter and was based on reaching minimum funding only. When you have to add 1.5 million worth of stretch goal content, that is also going to push the release date. That is simple common sense.
