How can I add recording time to a single recording not a series recording?

[Vinyl66]

If I set-up a series recording it allows me to add minutes to the recording time why can't I add time to a single recording? For example if I want to record a single show tomorrow I find it on the guide and hit record. Now I want to add a few minutes on the end of the show because I know it always runs over it's advertised time why can't I add the time? It doesn't gives to extra options for a single recording. The only time I can add time to a single recording is if the show is currently on then it allows me to add time but, not before the show is on. So what good does that do? Comcast allowed me to set-up extra options to a single recording.

[Keyboards]

Actually you can.  It's a bit clumsy but what you have to do is go to the DVR menu, select scheduled reordings, select the recording you want to extend, scroll through the menu and you will find an option to modify the start / end time.