Complex sentence: The first season was broadcast until May 27,2015, when, after the end of the last episode of the first season, a promo announced the second season, which began on September 27,2015 and ended November 29,2015.
Split into simpler sentences: The first season was broadcast until May 27,2015, when, after the end of the last episode of the first season, a promo announced the second season. The second season began on September 27,2015 and ended November 29,2015.