TAMM toolkit v0.2.0 is for base model older than base model in macOS 26 beta 4

Problem:

We trained a LoRA adapter for Apple's FoundationModels framework using their TAMM (Training Adapter for Model Modification) toolkit v0.2.0 on macOS 26 beta 4. The adapter trains successfully but fails to load with: "Adapter is not compatible with the current system base model." TAMM 2.0 contains export/constants.py with: BASE_SIGNATURE = "9799725ff8e851184037110b422d891ad3b92ec1"

Findings:

1. Adapter Export Process:

In export_fmadapter.py def write_metadata(...): self_dict[MetadataKeys.BASE_SIGNATURE] = BASE_SIGNATURE # Hardcoded value

1. The Compatibility Check:

- When loading an adapter, Apple's system compares the adapter's baseModelSignature with the current system model
- If they don't match: compatibleAdapterNotFound error
- The error doesn't reveal the expected signature

Questions:

- How is BASE_SIGNATURE derived from the base model?
- Is it SHA-1 of base-model.pt or some other computation?
- Can we compute the correct signature for beta 4?
- Or do we need Apple to release TAMM v0.3.0 with updated signature?