[nwtv2003]

I wonder if there were any cases of an ITV company forgetting to put up the test tones/card at the end of the night and triggering the caption? Would be a minor issue in the scheme of things but especially last thing at night after a works do I'd have thought it'd be an easy mistake to make.There were over 5000 such closedown a year across ITV so plenty of opportunity!

Not quite what we’re discussing, but here’s an example from 1985 after Granada closed down for the night, their own testcard/colour bars are transmitted with tone for a while before the blue caption arrives, even though there doesn’t appear to be any drop in tone. 

youtu.be