diff --git a/README.adoc b/README.adoc
index d384d649..00a0c1cf 100644
--- a/README.adoc
+++ b/README.adoc
@@ -1,5 +1,9 @@
 = Spring Statemachine
 
+NOTE: Master is now in a development of a `3.x` which may be extremely unstable.
+      Current stable release branch is `2.1.x`. Unless you are not planning to contribute to
+      initial reactive stories, PR's and issues should target towards `2.1.x` branch.
+
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 image:https://build.spring.io/plugins/servlet/wittified/build-status/SDG-MAS[Bamboo