Complex sentence: While the movie was intended to be released on April 21,2017, the release date was pushed back to September 1,2017.However, due to the film not having a definitive distributor as of yet, this release date has been pushed back indefinitely.
Split into simpler sentences: While the movie was intended to be released on April 21,2017, the release date was pushed back to September 1,2017. As the film does not yet have a definitive distributor yet, this release date has been pushed back indefinitely.