add pinned branch

Author: adamkarvonen

README.md

@@ -33,6 +33,8 @@ For more information, refer to our [blog post](https://www.neuronpedia.org/sae-b
 
 ### Installation
 
+**Versioning and Stability** This repository will continue to evolve as upstream libraries (such as SAE Lens) update. If you ever run into dependency conflicts or want an environment that reproduces all results from the paper, you can use the `stable_paper_version` branch. That branch includes a UV lockfile with fully pinned dependencies and provides a fully reproducible setup that will not change over time.
+
 **Stable Install (Recommended):** Set up a virtual environment with python >= 3.10 and clone the repo. To use our tested pinned dependencies, also use our `constraints.txt`.
 
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