lusone:
Industrial wasn't a new exam in 2016. They've used the same test since April 2013. See below.
Yes various exam committee meetings are routinely held every month. Most don't effect the release date. You have to look for the "exam review", "exam standard", "cut score" and similar meetings that are held after a new test is released - cross reference the exam specifications with when the latest exam was released.
This year all of the electrical exams, plus environmental and architectural are new for April 2018. All of those have "exam standard meeting"s May 18th-19th.