The default is 3 minutes late ending for recordings. 3 minutes or more late ending will cause the DVR to assign the other tuner to record the following show on the same channel. This is why I change the default to less than 3 minutes late. Then it will behave as you've described in the OP. However, if there is a recording scheduled on the same channel immediately following the first recording on the same channel, then, even if set to 1 or 2 minutes late, the first recording will end at 0 minutes late and begin recording the following show on the same channel at 0 minutes early, using the same tuner.
For some channel, such as MTV, 2 minutes early and 3 minutes is the ONLY way to guarantee that one will record the entire program as MTV is notorious for starting shows even 3 minutes early or starting 3 minutes late, but the 2 minutes early and 3 minutes late works 99% of the time, but the cost is that when recording programs back-to-back it requires both tuners that to record both shows" tuner 2 committed to 3 minutes late in all circumstances (not committed at 1 or 2 minutes late; it will use the same tuner 2), and Tuner 1 start for the 2nd following program. They overlap by recording some of the previous recording.
Change the defaults to 0 minutes late and 0 minutes early. You can still change those settings for each individual timer if necessary, but 0 and 0 will be the automatic default requiring no adjustments when creating timers.
None of this would be a problem is more channels stuck to the scheduled air times. They can do this if they want, right up to the very second. They all did this for decades, but now there is the pressure to use the trick of ending a show late to immediately go right into the next show on the same channel to prevent people from turning the channel, and then causing people to miss a few minutes of another show on a another channel, and, perhaps, deciding to stay tuned to that network since the missed the beginning of the show they wanted to tune to,
This trick was first used by Ted Turner who cleverly started (and subsequently ended) all his shows by 5 minutes of the hour and half-hour; AND IT WORKED!!!!
Most homes DO NOT have DVR's and are still viewing TV in the linear experience where these tricks do work to a fair degree, and since they are still the majority, it is those the networks go after. It becomes a big problem for those who use DVR's. Contrary to myth, the programmer have no dislike of the DVR, as DVR recordings are counted as a program viewed by the ratings systems. The prgrammers don't see it as a problem because they know that DVR's have end late features, not because they don't like DVR's.
Jimmy Kimmel once aired the final moments of his TiVo recording of the Bachelor to show how pissed he was that ABC ran the Bacelor longer than scheduled and just when they were about to reveal who was staying, the TiVo end recording prompt popped-up. It was funny and the first time anybody in show business brought this subject up, although Kimmel seemed a bit more pissed at TiVO, but all DVR's can fall victim to the lies of the programmers.
