The AP/DVC Preview weekend is this weekend. Last weekend was the Cast Member preview.
As for Soft Openings it really depends on Disney. They may have to make tweaks and modifications to ride mechanics so it may be open and closed as needed throughout the Soft Opening. Usually, Soft Openings go pretty smoothly and rides stays open quite a bit; however, there are no guarantees.
There is a press event scheduled for the official opening of the ride on April 7th.