Complex sentence: On March 24 1935, Chase and Sanborn chose this show to fill "The Chase and Sanborn Hour" on NBC, which last until September 17 1936, when the show moved to the CBS Radio Network.
Split into simpler sentences: On March 24 1935, Chase and Sanborn chose this show to fill "The Chase and Sanborn Hour" on NBC. This arrangement only lasted until September 17 1936, when the show moved to the CBS Radio Network.