Bridge randomly loses all generated previews

I use Bridge 12.0.2.252 on a 2019 16-in MacBook Pro running the latest MacOS Monterey to check focus on hundreds of portraits after a session.  I let it build 100% previews, but it will randomly just lose all generated previews (256, 1024, and full).  It happens while the app is open, sometimes while I'm scrolling through a session, sometimes if I've left the laptop to sleep.  

I've tried changing the cache folder to a different location, I've given the cache 275GB of space to use (I clear the cache after each session so it only needs to store previews for ~2500 photos at a time), I have it set to "Keep 100% Previews in Cache", not compact on exit, and not purge automatically.  I've experimented with each of those settings and it still randomly deletes all previews and I have to wait for them to rebuild.

Any suggestions?