Complex sentence: The automotive press has reported that the next full-size Cadillac will be the XTS Platinum concept which will create a single flagship sedan for the brand, which debuted at the Detroit International Auto Show in January 2010.
Split into simpler sentences: The automotive press has reported that the next full-size Cadillac would be the XTS Platinum concept which would create a single flagship sedan for the brand. The concept debuted at the Detroit International Auto Show in January 2010.