App updated - code changes pushed to Github - streamlit app on cloud stuck in oven after reboot(1hr) - changed Python version(3.9 to 3.10) and this seemed to get the app running.
Be careful with Python version changes. A small step like 3.9 to 3.10 can be fine, but a larger jump such as 3.9 to 3.15 could introduce package compatibility errors if dependencies are not updated to match. Only make that kind of change if you’re prepared to fix version and package issues immediately.
Hey there, thanks for sharing your experience and the helpful warning! 
You’re absolutely right—changing the Python version for a Streamlit Community Cloud app can resolve issues (like being stuck “in the oven”), but it’s important to be cautious. Minor upgrades (e.g., 3.9 → 3.10) are usually safe, but bigger jumps (like 3.9 → 3.15) can break dependencies if your requirements.txt isn’t updated accordingly. Always check that your packages support the new Python version before making the switch, and be ready to update or pin package versions as needed to avoid compatibility errors. For more on this, see the official Streamlit docs on upgrading Python and dependency management.
If you run into issues after a Python version change, check your logs for dependency errors, update your requirements.txt, and reboot or redeploy as needed. The “App settings” page (as shown in your screenshot) is the right place to change the Python version—just remember to save changes and monitor your app after the update. For more troubleshooting tips, see this forum thread and the Streamlit docs on rebooting your app.
Sources:
