Thanks for the detailed investigation and reproducible test case! We’ve reproduced the same issue on an iPhone 13 running iOS 27.0.1. This has been a major issue for our app, which relies on multiple encrypted Core ML models. Having to decrypt and initialize many models seems to increase the frequency of this failure. Once it happens, neither restarting nor reinstalling the app helps. Only a full iPhone reboot restores model loading. This issue is seriously affecting our app’s reliability. We hope Apple can investigate and fix the underlying resource cleanup problem. Thanks again for bringing attention to this!