diff --git a/README.md b/README.md
index e7fd9cb2..702ba904 100644
--- a/README.md
+++ b/README.md
@@ -34,6 +34,15 @@ This is a refactored and enhanced version of _DiffSinger: Singing Voice Synthesi
 - **Roadmap for future releases**: See [Project Board](https://github.com/orgs/openvpi/projects/1)
 - **Thoughts, proposals & ideas**: See [Discussions](https://github.com/openvpi/DiffSinger/discussions)
 
+## Important notice on experimental branches
+
+ONNX exporting pipelines, OpenUtau support and other deployment-related components are **supported ONLY FOR MAIN BRANCH**. Without in-depth knowledge on how and why DiffSinger code works, you can easily make things break just like many other machine-learning projects. All experimental branches are only intended for feature development, only a limited feature set is tested, and are **never meant to be deployed as ONNX models**. This wasn't clearly stated before and has caused us debugging headaches multiple times in the past, in some cases users had:
+
+  - distributed ONNX model that won't work in OpenUtau (possibly worked in their own modified revision) and led to mysterious bug report in OpenUtau repo (#xxxx)
+  - exported ONNX model with Torch 2.2 (which is unsupported), had a success (which is broken, ONNX export has A LOT of quirks we had to iron out with our code) and distributed the model, led to mysterious bug report in OpenUtau repo (#xxxx)
+
+### Please refrain from distributing model files generated by experimental branches, for the sake of developers' maintenance burden. This is NOT SUPPORTED.
+
 ## Architecture & Algorithms
 
 TBD