Complex sentence: Queen were due to go on the show but cancelled their appearance last minute and were replaced by the punk rock band the Sex Pistols and their entourage appeared at short notice on the "Today" show of 1 December 1976.
Split into simpler sentences: Queen were due to go on the show but cancelled their appearance last minute and were replaced by the punk rock band the Sex Pistols. The band, their entourage in tow, appeared at short notice on the "Today" show of 1 December 1976.