I recently shot in regular HD mode (MP4, 1080p, 28M) and something odd happened that I didn’t see in the documentation for the camera. It auto-split the file when it reached 4.3GB, actually it did this twice during the show.
I used to use a Sony camera that did this at 2GB due to file size limits of the operating system of Windows, and they were trying to make it easier for most customers. I assume that this 4.3GB limit is for people that make DVDs (4.7GB size limit).
I had shot in this mode to save time downsampling from 4K later. Since the split happened partway through a song, I had to do some geekery to join the two files and then extract the song. That took hours of running scripts, so I didn’t save any time. Would have been nice to know about it ahead of time, so I’m posting here for others.
The geekery (which worked but may have been overkill) was to turn the video files into M2TS files, save the audio files as WAV, use Audacity to join the WAV files, use tsmuxer to join the M2TS files, use ffmpeg to turn the joined WAV into AAC, then use ffmpeg to blend the audio with the video and extract the songs clips that had been arbitrarily divided by the camera. Sheesh!