In the case of the BBC» , time for more self-advertising?
This has of course absolutely nothing to do with railways, but...
In the case of the BBC, sometimes shows will over-run by a few seconds, or indeed minutes in some cases (especially ive shows), but they won't over-run enough to make a big deal out of it. For instance:
During the week I am not averse to watching "Outside Source" on the BBC News Channel between 2100 and 2200. Although the BBC News Channel also carries the 10 o'clock news, I tend to change to BBC1 at that point because the local news appears at the end of the show, whilst it doesn't on the News Channel.
The News Channel almost always runs a countdown sequence to the news at the top of the hour, involving an extended version of the news signature tune plus a countdown by seconds to the exact time of 2200. If they don't run that countdown, but just the news signature tune, you can rest assured that BBC1 is running late and the "10 o'clock news" will be starting at a few seconds past the hour.
If it is something more substantial (eg a live sport item "getting crucial" so the powers that be decide to stick with it), then an announcement will be made to say that the news or any other following programme is running late.
Not totally unlike, in fact, what happens on the railway -
"the 1918 service to Chittening Platform is delayed by 8 minutes" translates to "at the moment we think the train will be 8 minutes late."
"the 1918 service to Chittening Platform is delayed" translates to "we don't know what time its going to turn up either"