Will Sentry mode fill the drive with clips and not leave any room for Dashcam (RecentClips)? Do you periodically delete/format the drive? What's your process? I'm currently using Tesla provided 128gb drive and now only have 1hr (6gb) left for the RecentClips folder.
From the owners manual:
"When the internal storage reaches its limit, new recordings from Alert and Alarm event overwrite the older recordings."
"Recent Clips: When recording, Dashcam continuously saves footage to Recent Clips in 60-minute cycles. Footage is overwritten every hour unless you manually save it. Four videos are recorded for each clip, one from each camera (front, rear, left, and right)."
And finally,
"When the USB flash drive runs out of storage space, Sentry Mode and Dashcam can no longer save video footage. To prevent the flash drive from getting full, regularly move saved videos to another device and delete them from the flash drive."
So to directly answer your question, saved clips are the only ones not overwritten and would require action on your part.
Suggest you browse the user interface forum for memory media suggestions. The USB stick will eventually fail. Some prefer SSDs, some SD/Micro SD. Just depends on your environmental and use considerations.