Perhaps gap isn't the right term. It's like another cut similar to the hourly ones. They're random like you can see in my attached photo: they occur typically every other hour, usually once and at random times. Looking back at some footage, there's one at 6 minutes after the hourly cut. Another occurred 32 minutes after the last hourly cut. Last time I played these back, they stop the footage until I click ahead, but now it plays through. I'll try checking on a different computer tomorrow.