Complex sentence: Early episodes of the popular music-chart show "Top of the Pops" were wiped or never recorded and only broadcast "live", the last edition that was wiped from the BBC archives dating to September 8,1977.
Split into simpler sentences: Early episodes of the popular music chart show "Top of the Pops" were wiped or never recorded and only broadcast "live". The last edition that was wiped from the BBC archives dates to September 8,1977.