Hey there, thanks for the detailed question and welcome to the Streamlit community! 
Sorry to hear about your lost predictions data—that’s always a tough situation.
To answer your questions directly: Streamlit Community Cloud does not keep any recoverable snapshot, backup, or cache of your app’s local filesystem after a reboot or redeploy. Once the app restarts (for any reason: code push, system update, manual reboot, etc.), the container is reset and any files created or modified at runtime—including your predictions.sqlite3—are permanently lost. There’s no support-side option to recover these files, and only files tracked in your GitHub repo are restored on each deploy. Local files on Community Cloud are ephemeral and should not be used for persistent storage. For future-proofing, it’s strongly recommended to use an external, cloud-hosted database (like Supabase, Neon/Postgres, MySQL, MongoDB, or Google Sheets) for any data you want to persist across sessions and reboots. See the official Connecting to data docs for setup guides and best practices.
If you’d like step-by-step guidance on migrating your app to use a persistent database, just let us know! And if you have a minimum reproducible example or want help with code, please share your repo or code snippets so the community can jump in and help. Thanks for being part of the community, and don’t hesitate to ask more questions or share your learnings! 
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