C-day

For the military use of "C-Day" (or "Candy Day"), see Military designation of days and hours C-Day or Commercials Day, 1 July 2000, was the date at which UK broadcasters (with the exception of MTV UK and VH1 UK [1]) changed from requiring 4:3-aspect commercials, to requiring 16:9 Full Height commercials supplied to them, shot "14:9 safe" for those channels which in part (i.e. the analogue feeds of Terrestrial broadcasters) or in whole (many cable television and satellite television channels) continued to broadcast a 4:3 frame.
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