Complex sentence: Blackburn was also the first presenter of "Pick of the Pops" to go into the 21st century by featuring a chart from 2001 in April 2012, but he mainly featured years from 1957 to the early 1990s.
Split into simpler sentences: Blackburn was also the first presenter of "Pick of the Pops" to go into the 21st century by featuring a chart from 2001 in April 2012. However, he mainly featured years from 1957 to the early 1990s.