Delayed bcasts are hot fully recorded

Back in the days of Tivo you could put in the code for the program and it would record it whenever it started. With Xfinity, if the program is delayed (sports overtime, presidential message, etc.), the DVR blindly starts and stop recording using the scheduled record times not the bcast times so you lose all or part of the planned recording.  Not only does my DVR act this way but on-demand from Xfinity makes the same mistake!!!! Just tried East New York. Got the end of Equalizer and the first part of East New York.