> The question is… will Apple be constantly tweaking these models, or only during OS upgrades?

Certainly when new updates are released--going from macOS 26 to 26.1).

They can probably push model updates between releases if necessary.

Per the PDF in this post:

> “Adapters produced by the toolkit are fully compatible with the Foundation Models framework. However, each adapter is compatible with a single specific model version, meaning that a new adapter must be trained for each new version of the base model.”

Any changes should require retraining any LoRA adapters that has been built & distributed by third party developers, so they wouldn’t update the models outside OS updates at the drop of a hat I don’t think.

LoRA adapters can be distributed via Background Assets, but the base model itself should be version-locked to the OS build (e.g. iOS 26.0 → 26.1) and updates only when Apple ships a new OS image.